nippold, m. et al (2005) conversational versus expository

Marilyn A. NippoldLinda J. Hesketh

Jill K. DuthieTracy C. Mansfield

University of Oregon, Eugene

Conversational Versus ExpositoryDiscourse: A Study of SyntacticDevelopment in Children,Adolescents, and Adults

In this cross-sectional investigation, syntactic development was compared inconversational versus expository discourse in 120 typically developing children,adolescents, and adults, age 7 to 49 years. Each participant was asked todiscuss common topics such as school, family, and friends to elicit conversationaldiscourse and to explain the rules and strategies of a favorite game or sport to elicitexpository discourse. The results showed greater syntactic complexity in expositorydiscourse than in conversational for all age groups, supporting the view thatcomplex thought is driving the development of complex language. For both genres,growth in syntax continued throughout childhood and adolescence and into earlyadulthood (age 2029 years) and remained stable into middle age (age 4049years). The 2 best indicators of growth were mean length of T-unit and relativeclause production, both of which showed age-related increases into earlyadulthood. Another variable that was sensitive to growth was the total number ofT-units produced, a measure of language output. In general, older speakers talkedmore than younger ones regardless of genre. Despite the statistically significantgroup effects, there were wide individual differences. For example, in the expositorygenre, some of the younger children used rather elaborate syntax whereas someof the older adults spoke quite simply. Thus, it appears that individual variability canexist at all points along the age continuum, despite the trend toward greatersyntactic complexity as a function of increasing chronological age.

KEY WORDS: expository discourse, conversation, syntax development, children,adolescents, adults

L ater language development is characterized by growth in the abil-ity to communicate in flexible ways for diverse purposes (Ravid& Tolchinsky, 2002). This includes being able to use different dis-course genres, depending on the situation. One important genre is expository

discourse, the use of language to convey information (Bliss, 2002). Highlyvalued in academic settings, this occurs, for example, when a high school

studentexplainsthepurpose,steps,andoutcomeof a chemistry experimentor

instructs a group of peers in the use of a telescope for an astronomymeeting.

This contrasts with conversational discourse, a more interactive and less

formal genre (Crystal, 2002). Highly valued in social settings, conver-

sation occurs when a group of high school friends discuss the latest

fashions, movies, or CDs, exchanging opinions as well as sharing

Journal of Speech, Language, and Hearing Research Vol. 48 10481064 October 2005 AAmerican Speech-Language-Hearing Association10481092-4388/05/4805-1048

Cheryl Scott served as guest associate editor on this article.

information. Both genres require speakers to tap into

their cognitive and linguistic resources as they com-

municate their ideas in a clear and organized fashion.

However, expository discourse, with its emphasis on

speaking in a precise, monologic fashion (Berman &

Verhoeven, 2002), may heighten these demands, pos-

sibly resulting in greater linguistic complexity. In anycase, the ability to communicate in both genresby

considering the setting, purpose, and needs of the lis-

tener and readily adjusting to the situationis a mark

of speaker competence.

We designed the present study to compare thelinguistic complexity of conversational versus exposi-

tory discourse in children, adolescents, and adults andto identify broad developmental patterns. A primary

contributor to linguistic complexity is the speakersuse of syntax, the structural foundation of sentences(Crystal, 1996). Although little is known about the

development of syntax in expository discourse, muchhas been learned about its development in conversa-tion through longitudinal (e.g., Brown, 1973; Loban,

1976) and cross-sectional (e.g., Leadholm & Miller,1992; Miller, 1981; Paul, 1981) research. For exam-ple, Miller (1981) has shown that by age 5, most chil-

dren are conversing in complex sentences, have a meanutterance length of at least 6.0 morphemes, and makefew grammatical errors. Despite the impressive attain-

ments of a typical 5-year-old child, syntactic develop-ment in conversation continues well into adolescence,albeit at a more gradual pace than that which occurred

previously (Berman, 2004; Loban, 1976; Nippold, 1998).As Bates (2003) explained, beyond the preschool years,speakers are becomingmore fluent and efficient in the

process bywhichwords and grammatical constructionsare accessed in real time, and [are] learning how to use

the grammar to create larger discourse units (e.g.,writing essays, telling stories, participating in a longand complex conversation) (p. 15). Consistent with

this perspective, Loban (1976) argued that cognitivedevelopment and intellectual stimulation are far morelikely to accelerate syntactic growth than grammar

knowledge (p. 36) in older children and adolescents.

Two key markers of later syntactic development

include sentence length and clausal density (Nippold,

1993; Scott & Stokes, 1995). Beyond the preschool

years, sentence length is often measured with the

terminable unit, or T-unit (Scott, 1988). Hunt (1970)

defined the T-unit as one main clause plus any sub-ordinate clause or nonclausal structure that is at-

tached to or embedded in it (p. 4; for examples, see

Appendix A). Examining written language develop-

ment in school-age children and adolescents, Hunt

reported that the mean number of words per T-unit

was a more sensitive index of syntactic growth during

this period than other measures, such as the number of

words per clause or the number of clauses per T-unit.

In some studies, the communication unit (C-unit) has

been used to measure growth in syntax instead of the

T-unit. These two units are identical with the excep-

tion that the C-unit includes responses that lack an

independent clause when answering questions (Loban,

1976; for examples, see Appendix A).

Using the C-unit, Loban (1976) investigated syn-

tactic development in the context of conversational

discourse in 211 children who were followed longi-

tudinally from kindergarten through the 12th grade.

Every year, each child participated in a conversation

with an adult who recorded the childs language sam-

ple for detailed analyses. The results showed that mean

C-unit length increased as the children aged but at a

very slow rate. In a subgroup of students who repre-

sented a range of language proficiency levels, includ-

ing high, low, and average (Random Group, n = 35),

Loban reported the following mean C-unit lengths at

Grades 3, 5, 8, and 11, respectively: 7.62, 8.82, 10.71,

and 11.17 (p. 27). Despite its slow progression, mean

C-unit or T-unit length is considered to be an impor-

tant marker of later syntactic development (Hunt,

1970; Loban, 1976; Nippold, 1993; Scott, 1988; Scott

& Stokes, 1995; Scott & Windsor, 2000).

Another marker of later syntactic development is

clausal density, defined as the average number of clauses

(main and subordinate) per T-unit (Scott, 1988, p. 58).

Also called the subordination index, it is measured by

summing the total number of clauses (independent +

subordinate) and dividing by the total number of T-units

or C-units produced in a language sample. This marker

also increases gradually during the school-age and

adolescent years. Analyzing data from Lobans (1976)

longitudinal study, Scott (1988) reported the following

mean subordination indexes for Grades 3, 5, 8, and 11,

respectively: 1.22, 1.29, 1.39, and 1.52 (p. 59).

The appropriate use of subordination can enhance

the efficiency with which ideas are expressed. For

example, instead of producing a monotonous string of

independent clauses (e.g., I went to California. I saw a

movie. It was a new movie. Jeremy had recommended

it), a competent speaker can combine them into one

complex sentence that is rich in information yet clear

in meaning (e.g., When I went to California, I saw the

new movie that Jeremy had recommended). By age 5,

typically developing children are able to use all types

of subordinate clauses in conversation (Paul, 1981),

including relative, adverbial, and nominal (for exam-

ples, see Appendix A). However, additional refine-

ments continue to occur beyond the preschool years.

In Lobans (1976) longitudinal study, all three types

of subordinate clauses were used more frequently as

the students grew older, thereby contributing to the

Nippold et al.: Conversational Versus Expository Discourse 1049

increases observed in mean C-unit length and clausal

density through late adolescence.

To reiterate, much has been learned about syntac-

tic development in conversation, a topic that has been

studied for many years (e.g., Leadholm & Miller, 1992;

Loban, 1976; Miller, 1981; Scott, 1988). In contrast,

studies of expository discourse are just beginning to

emerge.

Berman and Verhoeven (2002) recently conducted

a cross-linguistic investigation that involved a com-

parison of narrative and expository discourse in seven

different languages (Dutch, English, French, Hebrew,

Icelandic, Spanish, and Swedish). Twenty native

speakers of each language from four different age

groups (910 years, 1213 years, 1617 years, and

2030 years) participated, for a total of 80 speakers

per country. Each participant viewed a short film

that depicted an interpersonal conflict. Afterwards,

speakers were asked to tell a story about a similar

situation they had experienced to elicit narrative dis-

course or to describe and comment on the problem

that was depicted in the film to elicit expository

discourse. Mean length of T-unit was used to measure

syntactic complexity of the samples. Across languages,

age-related increases in T-unit length occurred in both

genres, and complexity tended to be greater in exposi-

tory than in narrative discourse. Males and females

did not differ in their performance.

Verhoeven et al. (2002) conducted additional anal-

yses of these data, comparing the youngest children

(910 years) to the adults (2030 years). Verhoeven

et al. found that all types of subordinate clauses

relative, adverbial, and nominaloccurred more often

in expository discourse than in narrative discourse for

both age groups, across languages. They also found

that the use of subordinate clauses showed an age-

related increase in both genres. Relative clause pro-

duction was particularly sensitive to the effects of age

and genre: Adults used this type of clause far more

often than did children, and both groups used them

more frequently in expository discourse.

Similarly, Scott and Windsor (2000) elicited spoken

narrative and expository samples from American

English-speaking children who were 8 and 11 years

old (n = 20 per group). Two films were used to elicit the

samples, one a story about a young boy (narrative) and

the other a description of plant and animal life in the

desert (expository). Immediately after viewing a film,

the child was asked to provide an oral summary of it.

The results indicated that syntactic complexity, which

was based on mean length of T-unit, was greater in

expository than in narrative discourse for both age

groups, findings that were consistent with Berman and

Verhoevens (2002) findings.

In the present investigation, we compared the

syntactic complexity of expository and conversational

discourse from a developmental perspective, a topic

that had not been addressed previously. Children,

adolescents, and adults representing a wide range of

ages (749 years) participated in the study. Two types

of language samples, conversational and expository,were elicited from each speaker. The samples were

examined for syntactic complexity using measures that

have been used successfully in past research to identify

developmental and cross-genre differences (i.e., sen-

tence length and production of subordinate clauses;

e.g., Berman & Verhoeven, 2002; Hunt, 1970; Loban,

1976; Scott & Windsor, 2000; Verhoeven et al., 2002).

The conversational samples were similar to what

speech-language pathologists typically elicit in their

assessment of clients, encouraging discussion of com-

mon topics such as school or work, family, friends, and

pets. In contrast, the expository samples requested

the participants to explain the rules and strategies of

their favorite game or sport, a task developed for thepresent study. As Scott (1994) explained, there are many

varieties of expository discourse (e.g., descriptive,

procedural, causal, sequential, contrastive, compara-

tive) but the defining feature of this genre is that the

speaker attempts to convey information (Bliss, 2002).

Infinitely varied, this could include, for example, a

lecture on the differences between the composers Bach

and Mozart; a detailed account of how to operate acatamaran, bake a cake, or repair a light switch; or a

summary of the best bicycling routes in Europe.

Obviously, the speaker must have knowledge of the

topic and be able to express that information. In past

research, expository discourse samples were elicited

using films depicting interpersonal conflicts (Berman

& Verhoeven, 2002) or life in the desert (Scott &

Windsor, 2000), which the participants were asked toview and then to summarize. In pilot work, we

attempted to use a conflict task similar to that of

Berman and Verhoeven but found that it was too

difficult for our youngest participants (age 78 years).

Therefore, an alternative procedure, the favorite

game or sport task, was used to ensure that all par-

ticipants would be speaking from their own knowl-

edge base. Because games and sports are popular withpeople of all ages in the United States, we expected

that even the youngest children would have at least

one activity that they could describe. We also believed

that this procedure might yield a more realistic mea-

sure of participants skill with expository discourse

because it pertains to something that they have

experienced in their own lives.

As discussed above, past research has demon-

strated that syntactic complexity in conversational dis-

course gradually improves during the school-age and

1050 Journal of Speech, Language, and Hearing Research Vol. 48 10481064 October 2005

adolescent years and that key markers of growth

include increases in sentence length and clausal den-

sity, particularly in the use of relative, adverbial, and

nominal clauses (Loban, 1976; Scott, 1988; Scott &

Stokes, 1995). We predicted that similar age-related

changes would be evident in the expository genre but

that syntactic complexity would be greater in exposi-tory than in conversational discourse because of the

increased communicative demands the former seems to

place on the speaker. We also predicted that expository

discourse would have a lengthy developmental time

course, perhaps even longer than that for conversa-

tional discourse. For this reason, it was important to

examine development beyond adolescence and well

into adulthood. Little is known about language develop-ment in adults, because this has not been widely

investigated. However, Hunt (1970) reported that

mean length of the T-unit continued to increase beyond

adolescence and into early adulthood in written

language, and Berman and Verhoeven (2002) reported

similar findings with respect to spoken language.

However, no studies of syntactic development have

included middle-aged adults. In the present study, twogroups of adultsone younger (age 2029 years) and

one older (4049 years)were included. The findings

were expected to contribute to the knowledge base in

later language development, a topic of expanding in-

ternational interest (Berman, 2004).

The present study also represents an initialattempt to build a normative database in expository

discourse, one that could be used by speech-language

pathologists in their work with school-age children and

adolescents suspected of having language disorders.

When evaluating these young people, speech-language

pathologists frequently administer standardized lan-

guage tests and engage the students in conversation

for the purpose of examining oral language develop-ment (Evans & Miller, 1999). Often, the conversational

sample will be transcribed and analyzed using a

computer program such as Systematic Analysis of

Language Transcripts (SALT; Miller & Chapman,

2003), which calculates key syntactic, lexical, and

morphological variables, including mean utterance

length, total number of words and utterances pro-

duced, and the use of bound morphemes. A referencedatabase is available through SALT for comparing a

speakers conversational performance with that of age-

matched, typically developing peers.

Although this database can be helpful in docu-

menting oral language deficits and planning interven-

tion, there are cases where school-age children andadolescents perform adequately on standardized lan-

guage tests and exhibit normal conversational skills,

yet demonstrate difficulties with more complex speak-

ing tasks in natural settings (Nippold & Schwarz,

1996; Scott & Stokes, 1995). For example, academic

tasks, such as explaining the solution to a physics

problem or the steps involved in proving a theorem,

can be expected to challenge a speakers linguistic com-

petence more fully than conversation about simpler

topics that have been discussed many times before.

Information on how a child or adolescent performs inthis arena would be helpful in identifying subtle yet

troublesome difficulties in using a type of discourse

that is highly valued in school. Gillam, Pena, and

Miller (1999) discussed the role of expository discourse

as a language skill that contributes to academic

success. As such, they recommended that speech-

language pathologists assess the syntactic complexity

of expository discourse in upper elementary and highschool students. However, in the absence of a norma-

tive database, it is impossible to know what levels of

complexity are reasonable to expect at different ages.

In summary, in the present study we addressed

the following questions:

1. How does syntactic development differ in conver-

sational versus expository discourse?

2. What markers of syntactic growth exist for con-

versational versus expository discourse?

3. What changes occur in syntactic development

during early and middle adulthood?

4. What levels of performance can be expected of

children, adolescents, and adults?

MethodParticipants

A total of 120 individuals participated in this

investigation, including two groups of children, two

groups of adolescents, and two groups of adults. With

20 participants in each group, the mean ages (and

ranges) were as follows (in years;months): 8;1 (7;8

8;7), 11;4 (10;911;8), 13;9 (13;114;4), 17;3 (16;9

17;11), 25;6 (20;828;5), and 44;8 (40;849;9). The

children and adolescents were public school studentswho were attending an elementary school (Grade 2 or

5), middle school (Grade 8), or high school (Grade 11)

located in a low- to lower middleincome neighborhood

in western Oregon. According to their teachers, all stu-

dents were considered to be typical achievers who were

free of deficits in language, learning, and cognition. All

were of the appropriate age for their grade, and none

were receiving special education services. Theadultswereresidents of western Oregon who were individually re-

cruited by the graduate students who conducted the in-

terviews. Often, the adults were acquaintances of the

students or were referred to them by friends or relatives,


but no adult participants were students or professionals

in speech-language pathology or audiology. All adults

reported that they had graduated from high school,

and 37 out of 40 (93%) had attended at least 1 year of

college or university. On average, the adults had com-

pleted 3.5 years (range = 06.0 years) of formal education

beyond high school. Most of the adults in their 20s werestill attending college or university, and many were

employed (e.g., cook, bartender, secretary, salesperson).

Only a few of the adults in their 40s were students,

and most were employed (e.g., teacher, technician, man-

ager, electrician). On the basis of these factors, the adults

appeared to represent lower middle to middle-income

backgrounds.

All participants spoke English as their native

language. Information concerning race and ethnicity

was unavailable. Given that the study was not de-

signed to examine differences in the performance of

males versus females, no attempts were made to re-

cruit equal numbers of both sexes. For each age group,

the ratio of males to females was as follows: age 8 =1:0.67, age 11 = 1:1.50, age 13 = 1:1.22, age 17 = 1:3.0,

age 25 = 1:1, and age 44 = 1:1.86. The entire sample

of 120 participants included 51 males (43%) and 69

females (57%), a ratio of 1:1.35.

ProcedureGraduate students majoring in communication

disorders and sciences individually interviewed all

participants. In total, 53 graduate students (2 men,

51 women) conducted the interviews as part of a course

requirement. Each graduate student completed be-

tween one and three interviews with a child, adoles-

cent, or adult. All interviewers were carefully trained

by the investigators to maintain confidentiality, ad-

here to the examination protocol, and transcribe thelanguage samples carefully. All testing took place in a

quiet area, free of distractions. The children and ado-

lescents were tested at their schools, whereas the adults

were tested at either the university speech, language,

and hearing clinic; their workplace; or a residence.

Each session began with a brief introduction toexplain the procedures, establish rapport, and secure

the participants written agreement to take part in

the study. Next, a sample of conversational discourse

was elicited, which required about 5 to 8 min to

complete. The interviewer began by asking the par-

ticipant to talk about common topics such as school

or work activities, family members, friends, and pets.

When a participant showed interest in a topic, theinterviewer asked questions or made positive com-

ments to stimulate additional discussion. The conver-

sations continued until the participant had finished

talking and appeared ready to move to the next

activity. Then, the interviewer presented the favorite

game or sport task, which was designed to elicit a

sample of expository discourse. This also required

about 5 to 8 min and asked the participant to select a

favorite game or sport and to discuss it in detail. A

series of prompts were used to ensure that all speakers

addressed the same issues and thought about theirtopics carefully. To elicit the sample, the interviewer

read the following script aloud:

I am hoping to learn what people of different ages

know about certain topics. There are no penaltiesfor incorrect answers.

A. What is your favorite game or sport?

B. Why is [e.g., chess] your favorite game?

C. Im not too familiar with the game of [chess],

so I would like you to tell me all about it. For

example, tell me what the goals are, and how

many people may play a game. Also, tell me

about the rules that players need to follow.

Tell me everything you can think of about the

game of [chess] so that someone who has neverplayed before will know how to play.

D. Now I would like you to tell me what a playershould do in order to win the game of (chess).

In other words, what are some key strategies

that every good player should know?

Following each prompt, the interviewer paused,

displayed interest in the response, and allowed the

speaker as much time as necessary to complete theresponse. If a speaker failed to address a question or

requested that one be repeated, the interviewer posed

the question again. All discourse samples were audio-

recorded using a standard, portable cassette player.

Data Transcription and AnalysisEach conversational and expository sample was

transcribed by the same graduate student who had

conducted the interview. The samples were broken

into T-units, defined as an independent clause with

any accompanying subordinate (dependent) clauses(Hunt, 1970). Any fragments (incomplete T-units) or

mazes were placed within parentheses and ignored for

purposes of the present study. Following this, one of

the investigators listened to each audiotape a second

time to verify the accuracy and completeness of the

transcriptions, and made any necessary corrections.

Then, a second investigator entered the samples into

the SALT (Miller & Chapman, 2003) computer programand individually coded the samples so that SALT

would count all independent clauses and three types

of subordinate clauses: relative (RC), adverbial (AVC),

and nominal (NOM). In coding the different types of


clauses, the guidelines shown in Appendix A were used.

To simplify the coding process, only finite clauses

(both independent and subordinate) were identified.

As defined by Quirk and Greenbaum (1973), a finite

clause always contains a subject as well as a predi-

cate (p. 310). Thus, in the present study, all nonfinite

clauses (those that did not contain a subject) wereignored. After coding a sample, the same investigator

double-checked all codes and made any necessary cor-

rections. A third investigator performed a final check

of all codes and flagged any disagreements with the

initial codings. For each type of clause, the percent-

age of disagreement between the two investigators

was as follows: independent clauses = 1%; RCs = 1%;

AVCs= 1%; and NOMs = 6%. All disagreements wereresolved through discussion so that 100% agreement

was attained for all clause types. In addition to the

independent and subordinate clauses, SALT counted

the total number of T-units and calculated the mean

length of T-unit in words for each sample. The data

then were entered into the SAS system (SAS Institute,

2001), which determined the percentage of T-units

that contained each type of subordinate clause. Percent-ages rather than raw numbers were used to control

for differences in sample length. SAS also determined

the subordination index, a measure of clausal den-

sity. This consisted of the total number of clauses

(independent + RC + AVC + NOM) divided by the to-

tal number of T-units in a sample (Scott, 1988). Again,

in determining the total number of clauses, only fi-

nite clauses were counted (see Appendix A).

ResultsBoth tasks were effective in eliciting discourse

from all age groups. Regarding the favorite game or

sport task, a wide range of activities was discussed,

including games such as poker, chess, and Clue, and

sports such as basketball, football, baseball, track and

field, cross-country running, swimming, wrestling,

hockey, tennis, soccer, golf, and rowing. For each of

the six age groups, the following variables are reportedin Tables 1 and 2, respectively, for conversational and

expository discourse: total number of T-units, mean

length of T-unit in words, percentage of T-units con-

taining RCs, percentage of T-units containing AVCs,

percentage of T-units containing NOMs, and clausal

Table 1. Measures of language production for conversational discourse (n = 20 per group).

Measure Age 8 Age 11 Age 13 Age 17 Age 25 Age 44

Total T-unitsM 33.95 25.45 38.25 61.50 50.80 60.10SD 13.31 17.20 20.98 31.54 23.88 34.45Range 962 468 684 19140 696 17151

Mean length of T-unitM 6.74 7.31 6.88 8.33 9.86 9.56SD 0.86 1.62 0.93 1.27 2.09 2.01Range 4.428.44 3.6710.56 5.568.52 5.8310.32 6.0013.44 6.8815.16

Relative clause usea

M 3.42 5.00 4.43 8.29 10.20 8.68SD 3.61 6.41 3.78 4.64 8.12 8.22Range 011.11 022.22 012.12 020.93 022.92 036.84

Adverbial clause usea

M 7.28 10.84 5.50 10.99 10.43 12.04SD 4.67 9.37 4.77 4.63 7.73 6.19Range 016.67 033.33 016.98 018.60 022.58 025.00

Nominal clause usea

M 7.04 9.42 6.58 11.05 18.13 17.71SD 7.00 10.86 6.03 6.01 11.99 10.14Range 023.33 043.75 020.75 022.73 053.16 5.5638.33

Clausal densityM 1.18 1.25 1.17 1.30 1.39 1.38SD 0.09 0.22 0.09 0.11 0.21 0.19Range 1.001.37 1.001.75 11.42 1.081.56 1.081.82 1.121.77

aReported as percentage of T-units per sample.


density. To assist the reader in visualizing these data,

they are also presented in Figures 1 through 6.

To examine the effects of age and discourse genre,

a repeated measures analysis of variance was per-

formed on each variable. For total number of T-units

and mean length of T-unit in words, raw scores served

as the dependent measure; however, for each type ofsubordinate clause, raw percentage scores served as

the dependent measure. Bonferroni corrections were

used for multiple comparisons (adjusted a = .008). Ef-fect sizes were computed using the eta coefficient

(h; Meline & Schmitt, 1997) and were interpreted as

Table 2. Measures of language production for expository discourse (n = 20 per group).

Measure Age 8 Age 11 Age 13 Age 17 Age 25 Age 44

Total T-unitsM 33.05 35.30 36.15 44.00 51.55 60.55SD 25.36 17.40 19.12 27.28 31.95 23.30Range 1097 1677 988 12113 9128 11109

Mean length of T-unitM 8.59 9.29 8.68 10.59 11.04 11.46SD 1.89 0.90 1.64 1.60 1.39 1.11Range 6.0713.62 8.0412.05 6.5314.05 7.5813.65 8.2113.24 10.0815.17

Relative clause usea

M 6.50 6.14 5.20 11.27 11.60 14.44SD 6.91 4.84 5.10 6.29 6.20 8.28Range 021.43 019.61 018.18 3.7030.43 022.97 029.55

Adverbial clause usea

M 25.62 22.61 23.50 27.22 22.51 25.60SD 19.49 10.58 13.97 18.12 9.80 10.77Range 076.19 6.2541.18 3.3354.55 4.3579.49 7.5947.06 10.2048.94

Nominal clause usea

M 10.24 16.67 13.11 17.85 19.79 19.06SD 8.78 7.68 12.37 17.62 9.89 6.99Range 033.33 2.7033.33 044.44 3.8583.33 039.36 8.7733.03

Clausal densityM 1.42 1.45 1.42 1.56 1.54 1.59SD 0.23 0.16 0.20 0.28 0.15 0.14Range 1.001.90 1.261.75 1.122.05 1.242.33 1.241.89 1.301.89

aReported as percentage of T-units per sample.

Figure 1. Language output (total T-units produced) forconversational and expository discourse for each age group.

Figure 2. Mean length of T-unit (in words) for conversational andexpository discourse for each age group.


follows: small = .10.23, medium = .24.36, and large =

.37.71 (Cohen, 1969, p. 276). When differences were

statistically significant, Tukeys studentized range

(honestly significant difference) test ( p = .05) was used

to determine where they occurred.

For total number of T-units, a statistically signifi-cant main effect was obtained for group, F(5, 114) =7.80, p G .0001, h = .50, but not for genre, F(1, 114) =0.32, p > .05, h = .05. The effect size for group waslarge. The interaction between group and genre wasnot statistically significant, F(5, 114) = 1.72, p > .05,h = .26. Tukey tests indicated that for conversation,the 44-year-old adults outperformed the 11- and 8-year-old children, the 25-year-old adults outperformedthe 11-year-old children, and the 17-year-old adoles-cents outperformed the 13-, 11-, and 8-year-old chil-dren. For explanation (i.e., expository discourse), the44-year-old adults outperformed the 13-, 11-, and8-year-old children. Thus, the findings demonstratedan age-related increase in language output for both

genres. Fortunately, the two types of discourse sam-ples did not differ in total number of T-units producedfor any group, making it reasonable to compare thetwo genres on key syntactic variables.

For mean length of T-unit, statistically significantmain effects were obtained for group, F(5, 114) = 22.55,p G .0001, h = .71, and genre, F(1, 114) = 129.35, p G.0001, h = .73. The effect size for group and genre waslarge. The interaction between group and genre wasnot statistically significant, F(5, 114) = 0.83, p > .05,h = .19. Tukey tests indicated that for conversation, the44- and 25-year-old adults outperformed the 13-, 11-,and 8-year-old children; the 25-year-old adults out-performed the 17-year-old adolescents; and the 17-year-old adolescents outperformed the 13- and 8-year-oldchildren. For explanation, the 44- and 25-year-old adultsoutperformed the 13-, 11-, and 8-year-old children,and the 17-year-old adolescents outperformed the 13-and 8-year-old children. Thus, mean length of T-unitsteadily increased into adulthood in both genres andwas greater in explanation than in conversation

Figure 3. Relative clause use for conversational and expositorydiscourse for each age group.

Figure 4. Adverbial clause use for conversational and expositorydiscourse for each age group.

Figure 5. Nominal clause use for conversational and expositorydiscourse for each age group.

Figure 6. Clausal density for conversational and expositorydiscourse for each age group.


for all groups. As shown in Figure 2, the growthrate for mean T-unit length was nearly identical inboth genres.

For relative clauses, statistically significant main

effects were obtained for group, F(5, 114) = 9.00, p G

.0001, h = .53, and genre, F(1, 114) = 11.28, p = .0011,h = .30. The effect size was large for group and mediumfor genre. The interaction between group and genre

was not statistically significant, F(5, 114) = 1.02, p >

.05, h = .21. Tukey tests indicated that for conversa-tion, the 25-year-old adults outperformed the 13- and

8-year-old children. For explanation, the 44- and

25-year-old adults outperformed the 13-year-old chil-

dren. Thus, in addition to an age-related increase in

RC production, all groups showed greater use in ex-planation than in conversation.

For AVCs, a statistically significant main effect

was obtained for genre, F(1, 114) = 120.69, p G .0001,

h = .72, but not for group, F(5, 114) = 0.87, p > .05, h =.19. The effect size for genre was large. The interaction

between group and genre was not statistically signifi-cant, F(5, 114) = 0.76, p > .05, h = .18. For every group,AVCs were used more often in explanation than in con-

versation, but there were no age-related increases in use.

For NOMs, a statistically significant main effect

was obtained for group, F(5, 114) = 6.57, p G .0001, h =.47, and genre, F(1, 114) = 12.62, p = .0006, h = .32. Theeffect size was large for group and medium for genre.

The interaction between group and genre was not

statistically significant, F(5, 114) = 0.77, p > .05,

h = .18. Tukey tests indicated that for conversation,the 44- and 25-year-old adults outperformed the

13-, 11-, and 8-year-old children; however, for explana-

tion, the groups did not differ. The failure to find sig-

nificant group differences for explanation may be dueto the conservative nature of the Tukey test, which

tightly guards against Type I error (Winer, 1971).

Thus, the findings indicated an age-related increase

in NOM production only in conversation and that all

groups used NOMs more often in explanation.

For clausal density, a statistically significant main

effect was obtained for group, F(5, 114) = 7.78, p G

.0001, h = .50, and genre, F(1, 114) = 100.07, p G .0001,h = .68. The effect size was large for both group andgenre. The interaction between group and genre was

not statistically significant, F(5, 114) = 0.60, p > .05, h =.16. Nevertheless, Tukey tests indicated that for

conversation, the 44- and 25-year-old adults outper-

formed the 13- and 8-year-old children, but for ex-

planation, the groups did not differ. Again, this result

may stem from the conservative nature of the Tukey

test (Winer, 1971). Thus, although clausal density

showed an age-related increase only in conversation,

it was greater in explanation than in conversation for

all groups.

Because mean length of T-unit has long been

regarded as a key marker of syntactic development,

and one that reflects the use of subordination (Hunt,

1970), we decided it was important to examine the

relationship of T-unit length to the different types of

subordinate clauses that were examined in this study.

For each genre, Pearson productmoment correlation

coefficients were calculated for each age group sepa-

rately, using each participants mean length of T-unit

and raw percentage score on each type of subordinate

clause and the clausal density score. As shown in Table 3,

many of the coefficients were statistically significant,

particularly for AVC production and for clausal

density. This indicates that mean length of T-unit

is a good predictor of the use of subordination in both

conversational and expository discourse genres.

Given the usefulness of the T-unit as a general

index of syntactic proficiency, independent t tests

comparing the performance of males and females wereconducted for both genres. The results were not sta-

tistically significant for either genre: conversation,

t(118) = 0.28, p = .7795, and explanation, t(118) =

0.57, p = .5727. These findings are consistent with past

research in expository discourse (Berman & Verhoeven,

2002) that has indicated no gender differences.

Table 3. Pearson productmoment correlation coefficients between mean length of T-unit and each of the clausal variablesfor conversational (Con) and expository (Exp) discourses (n = 20 per group).

Age 8 Age 11 Age 13 Age 17 Age 25 Age 44

Con Exp Con Exp Con Exp Con Exp Con Exp Con Exp

Mean length of T-unit 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00Relative clause use .46* .41 .48* .08 .21 .57** .61** .14 .67** .26 .81**** .18Adverbial clause use .59** .79**** .72*** .40 .40 .56** .85**** .58** .65** .20 .36 .27Nominal clause use .02 .07 .60** .56** .24 .47* .10 .46* .45* .07 .49* .36Clausal density .48* .83**** .75**** .57** .49* .83**** .67** .69*** .75*** .19 .75*** .49*

*p G .05. **p G .01. ***p G .001. ****p G .0001.


Finally, it is enlightening to examine what the

participants actually said when speaking in the con-

versational and expository genres. Appendix B con-

tains portions of transcripts recorded from speakers

representing each of the six age groups. Each type of

clause is indicated immediately after each main verb.

Mean length of T-unit obtained by the speaker, on thebasis of the complete sample, is shown. Differences in

utterance length and syntactic complexity can be ob-

served between genres and, to a lesser degree, across

age groups. It is important to note that these exam-

ples illustrate how the favorite game or sport task

appears to stimulate the speakers to use a level of

syntactic complexity that is not apparent from their

conversational discourse.

DiscussionThe purpose of this cross-sectional study was

to examine syntactic development in conversational

and expository discourse over a wide age range (7

49 years). The main objective was to identify and com-

pare key markers of syntactic growth across participant

ages and discourse genres and to determine if growth

continued beyond adolescence and into early and

middle adulthood. We expected that syntactic com-plexity would be greater in expository than in con-

versational discourse but that growth would be

evident in both genres.

The findings indicated that for both genres, syntax

continued to develop beyond adolescence and into earlyadulthood (2029 years) and remained stable into

middle age (4049 years). Although we predicted that

expository discourse might undergo a longer develop-

mental time course than conversational discourse,

there was no evidence for continued growth beyond

early adulthood in either genre. The two best indica-

tors of growth were mean length of T-unit and RC

production. In contrast to the other measures (i.e., theuse of AVCs, NOMs, and clausal density), these two

measures showed age-related increases into adulthood

in both genres, and the effect sizes for group were

large. Berman and Verhoeven (2002) and Verhoeven

et al. (2002) also reported that mean length of T-unit

and RC production were particularly sensitive to de-

velopmental gains in expository discourse in their

cross-linguistic study. In the present study, anothervariable that was sensitive to age-related growth was

the total number of T-units produced, a measure of

language output. In general, older speakers talked

more than younger ones regardless of genre. NOM

production also increased in relation to chronological

age but in conversational discourse only.

It was interesting that AVCs, used by all sixgroups more frequently in explanation than in con-versation, did not show any age-related increases. It isnotable that even the youngest children in the studyused this type of clause as often as the adults, re-gardless of genre. Similarly, the youngest group usedNOMs as often as the adults when speaking in theexpository genre. Thus, the expository discourse taskappeared to stimulate even the youngest children toemploy these types of clauses when explaining theirfavorite game or sport.

Clausal density, recognized as a key marker of

syntactic development in conversation (Scott, 1988;

Scott & Stokes, 1995), also proved sensitive to growth,

but not in expository discourse. Although unexpected,this finding seems to have resulted from the fact that

all six age groups used all three types of subordinate

clauses to a greater extent in expository than in

conversational discourse. Thus, it cannot be assumed

that key markers of syntactic development are identi-

cal for both genres. It is important that this lack of

sensitivity to growth in the expository genre not be

interpreted as a negative result. On the contrary, it is

positive in showing that even young, school-age

children are able to use subordination as frequently

as middle-aged adults, but young children require a

task that is cognitively challenging to reveal their

syntactic competence. It is possible that the favorite

game or sport task is especially effective in eliciting

subordinate clauses as speakers explain the special

conditions of their chosen activity (e.g., If your

opponent hits the ball out of bounds, you get a point).

For this reason, it cannot be assumed that other types

of expository tasks would yield the same outcome. For

example, Verhoeven et al. (2002) reported an age-

related increase in the use of subordinate clauses when

10-year-old children and young adults were compared

in their descriptions of interpersonal conflicts. Thus,

we emphasize that the results of the present study

pertain to one type of expository discourse, explaining

the rules and strategies of a favorite game or sport. It is

possible that different results might be obtained with

other types of expository tasks (e.g., summarizing the

outcome of an election campaign; comparing and

contrasting two brands of candy, clothing, or soda;

explaining why babies cry). Hence, it will be important

in future research to examine syntactic development

by comparing different types of expository discourse

tasks.

As predicted, expository discourse elicited greatersyntactic complexity than conversational. For each of

the six age groups, performance in the expository

genre exceeded performance in the conversational

genre on each of the relevant variables: production of


all types of subordinate clauses (RC, AVC, NOM),

clausal density, and mean length of T-unit. Accord-

ingly, striking differences in syntactic complexity

between conversational and expository discourse can

be seen in the examples in Appendix B. Consider

Speaker 1, an 8-year-old boy. When talking about the

game of poker, he evidenced a sophisticated level of

conditional (ififthen) reasoning where two related

circumstances, expressed as AVCs (If the other guy

decides to play a royal flush and you have a royal flush

with a pair of acesI), can result in a positive outcome(Iyoure gonna win). This level of complexity neveroccurs in his conversational sample, where he talks

about dogs and his stepsisters. Similarly, Speaker 2, a

10-year-old girl, evidenced conditional reasoning,

expressed through multiple AVCs per T-unit, in

describing the game of chess (e.g., If the bishop was

right here and the king was right here, that would be

check), structures that never occurred in the conver-

sation about her sister.

Additional examples of conditional reasoning

expressed by subordination are apparent in the expos-

itory samples of Speaker 5, a 26-year-old man who

talked about cross-country racing tactics (e.g., When

you have a lot of corners in a race and you can turn a

corner and not be seen by your opponentI), and ofSpeaker 6, a 40-year-old man who produced six AVCs

within one 60-word T-unit to describe a strategy for

winning a basketball game (e.g., So if one team tried

to score a goalI). As with the 8- and 10-year-oldchildren, neither of these adults evidenced conditional

reasoning in their conversational samples, both of

which involved discussions about household pets.

NOM production also occurred more frequently in

expository discourse than in conversational discourse,

enabling speakers to elaborate on some fundamental

concepts of their game or sport. This can be seen, for

example, when Speaker 3, a 14-year-old boy who was

discussing baseball, distinguished a home run (And a

home run is when you hit it over the fence or you hit it

and you make it all the way around the bases without

stopping) from a grand slam (A grand slam is when

the bases are loaded and someone hits a home run and

everyone goes in). In contrast, his conversational sam-

ple gave no evidence of his ability to use these clauses.

It was impressive also when speakers were able to

use all three types of subordinate clauses in a single

T-unit, as when Speaker 4, a 17-year-old girl who was

explaining the shot put, described how to do a half spin

(And if you do a half spin, what you do isI). Re-markably, this 60-word T-unit contained two NOMs,

five RCs, and one AVC.

These examples also illustrate how the use ofvarious types of subordinate clauses contributes to

increases in mean length of T-unit, a pattern that is

consistent with the correlation coefficients reported in

Table 3. Loban (1976) reported similar findings in

relation to conversational discourse during the school-

age and adolescent years. The present findings repli-

cate that pattern and extend it not only to expository

discourse but to adulthood as well. Hence, it isinteresting to observe how mean T-unit length is

markedly greater in expository discourse than in

conversational. This is most obvious for Speaker 3,

whose mean T-unit length was 6.26 words in conver-

sation but 9.96 in explanation, a difference of 3.70

words. Similar patterns occurred for the other speak-

ers, where the differences in words per T-unit were as

follows: Speaker 1 = 2.08, Speaker 2 = 1.39, Speaker4 = 3.43, Speaker 5 = 3.1, and Speaker 6 = 2.80.

The results of the present study are consistent

with the views expressed by other investigators (e.g.,

Bates, 2003; Loban, 1976) that later syntactic develop-

ment is not primarily a matter of acquiring new

grammatical structures. Rather, it seems to be morea process of learning how to use existing structures

with greater efficiency and dexterity to communicate

complex thoughts in a way that is clear and informa-

tive. The expository task provided evidence that even

the youngest children were capable of speaking in a

sophisticated manner, and many of them performed

quite well on this task. As a group, however, they were

not performing at an adult level in all respects. Whatseems to change as a function of increasing chro-

nological age is knowledge of the topic at hand. In

general, younger speakers displayed less knowledge of

their favorite game or sport and had less to say about

it than older ones, giving the impression that com-

plex thought was driving the use of complex syntax. A

clear illustration of this pattern was observed when

an 8-year-old boy and a 40-year-old man (Speaker 6 inAppendix B) were asked an identical question about

basketball by their respective interviewers: Tell me

what a player should do in order to win the game of

basketball. In other words, what are some key strat-

egies that every good player should know? The 8-year-

olds entire response was as follows: Well, how to win

is you have to score more points than the other team.

Mostly like all games [laughs]. In contrast, the adultoffered three different strategies to answer this ques-

tion and explained each one in great detail (two of

which are contained in Appendix B).

It is important, however, to refrain from over-

generalizing the results on the basis of age, as some of

the youngest children (e.g., Speaker 1 in Appendix B)offered elaborate responses, whereas some of the oldest

adults offered rather simple ones. Thus, it appears that

individual exceptions can occur at both ends of the age

continuum despite the general trend toward greater


syntactic complexity as a function of increasing chro-

nological age. Indeed, despite the statistically signifi-

cant group effects, speakers within every age group

demonstrated considerable variability in performance.

For example, inspection of the ranges and means

reported in Table 2 indicates that there were 11-year-

old children whose expository performance (e.g., meanlength of T-unit) resembled that of the average 25-

year-old adult, just as there were speakers in their 20s

and 40s whose performance (e.g., RC use) resembled

that of the average 8- or 11-year-old child. Similar

patterns can be observed in all age groups. Because

speakers of any age appear to differ widely in the use of

complex syntax during the years between middle

childhood and middle adulthood, the means reportedin Tables 1 and 2 should be thought of as estimates

rather than as standards or norms. This is particularly

true considering the means are based on fairly small

sample sizes and represent the performance of English-

speaking children, adolescents, and adults living in

western Oregon. In addition, it is unknown how these

speakers might perform on other types of expository

tasks.

Nonetheless, it is notable that this pattern of wide

individual differences within groups has been observed

in early childhood as well. Bates and her colleagues

(Bates, 2003; Bates, Dale, & Thal, 1995) reported strik-

ing examples of this in their studies of the grammatical

development of healthy, middle-class toddlers. As theyemphasized, these large individual differences pose

serious difficulties for the notion of identifying deficits

in the language development of young children. As the

present study indicates, large individual differences

pose similar challenges for identifying deficits in older

children, adolescents, and adults. To solve this prob-

lem, it will be necessary to recruit large numbers of par-

ticipants for each age group (e.g., 100+) so that validpercentiles (e.g., 10th, 25th, 50th, 75th, 90th) and stan-

dard scores on each measure can be established. It will

be important also to recruit participants from diverse

cultural, linguistic, and socioeconomic backgrounds

and to build those differences into the normative

database. Then, to account for individual differences,

it will be necessary to examine expository discourse in

conjunction with other cognitive and linguistic skillssuch as verbal reasoning, spoken and written language

comprehension, and academic achievement. It will be

interesting also to perform more fine-grained analyses

of the data. This could include an examination of non-

finite clauses, noun- and verb-phrase elaboration, and

later developing infinitive, gerundive, and participial

phrases. The interface between syntactic and lexical de-

velopment could also be investigated by charting the useof later developing adverbial conjuncts (e.g., moreover,

similarly) to achieve cohesion across clauses.

We emphasize the importance of recruiting larger

numbers of participants in future research, given some

of the findings of the present study. For example, it is

surprising that the 13-year-old adolescents appeared

to perform below the 11-year-old children, especiallyin mean T-unit length and the use of subordination(see Figures 26). Although not statistically significant,this slight drop in performance is counter to what hasbeen observed in past research. For example, Loban(1976) found gradual increases in mean C-unit lengthand subordination when comparing Grades 5 and 8,and other investigators have reported that otheraspects of language (e.g., semantics) undergo rapidgrowth as children make the transition into adoles-cence (e.g., Nippold & Haq, 1996; Nippold, Hegel,Sohlberg, & Schwarz, 1999; Nippold & Rudzinski,1993). Larger sample sizes would help to determinethe validity of this unexpected drop.

Developmental studies of expository discourse are

just emerging. It is clear that many additional inves-

tigations remain to be conducted in this arena, par-

ticularly in building a database that can be used by

speech-language pathologists to assess the develop-

ment of discourse in children, adolescents, and adults.

Studies that attempt to account for the wide individual

differences observed within age groups will be most

informative, particularly when they include speakers

who exhibit patterns of delayed, average, and even

superior language development.

Acknowledgments

This project was partially supported by Grant

2P50DC02746-06A1 from the National Institute on Deafness

and Other Communication Disorders and a Summer Faculty

Research Award from the University of Oregon, awarded

to Marilyn A. Nippold.

We express sincere gratitude to the children,

adolescents, and adults who participated in this research

project and to the teachers and administrators who granted

permission for the testing to take place at their schools.

The assistance of Communication Disorders and Sciences

graduate students in collecting and transcribing the

language samples is also greatly appreciated.

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Received May 25, 2004

Revision received August 25, 2004

Accepted January 9, 2005

DOI: 10.1044/1092-4388(2005/073)

Contact author: Marilyn A. Nippold, CommunicationDisorders and Sciences, College of Education, University ofOregon, Eugene, OR 97403. E-mail: [email protected]


Appendix A. Definitions and examples of T-units, C-units, fragments, and clauses.

T-UnitA T-unit contains one independent (main) clause and any dependent (subordinate) clauses or nonclausal structures that are attached to it orembedded within it (Hunt, 1970). For example, the utterance Bill bought a new bicycle before he went to Europe is one T-unit that contains anindependent clause (Bill bought a new bicycle) and a dependent clause (before he went to Europe). In contrast, the utterance Bill went toFrance and then he went to Italy consists of two T-units because it contains two independent clauses joined by the coordinating conjunction and.Whenever a coordinating conjunction (e.g., and, but, so) initiates an independent clause, that clause is considered to be a new T-unit.

C-UnitA C-unit is identical to a T-unit but includes responses that lack an independent clause when answering a question (Loban, 1976). For example,the response yes to the question Did Jack drive? is one C-unit.

FragmentA fragment is an utterance that lacks a main verb and/or a subject; therefore, it is not an independent clause (Crews, 1977). It does not answer aquestion. For example, the following utterances are fragments: going down the road, the other day, 2 weeks later.

Independent (Main) ClauseAn independent clause contains a subject and a main verb and makes a complete statement (Crews, 1977). For example, the following are bothindependent clauses: Mother rode her bicycle to work today, and It started to rain late last night.

Dependent (Subordinate) ClausesA dependent clause contains a subject and a main verb but does not make a complete statement; therefore, it cannot stand alone. There are threemain types of dependent clauses: relative, adverbial, and nominal (Crews, 1977; Quirk & Greenbaum, 1973):

1. A relative clause (i.e., adjective clause) acts like an adjective and modifies the noun that precedes it: for example, The cat that was sleepingon the couch was content.

2. An adverbial clause acts like an adverb and modifies a verb. It often describes a condition or cause and begins with a subordinate conjunction:for example, Unless we can reach Los Angeles by eight oclock, well miss the concert.

3. A nominal clause is a noun-like element that can serve as either the subject of a sentence (e.g., Whatever she told you about the weddingwas a great exaggeration) or its object (e.g., I told her what she needed to hear). Nominal clauses often begin with wh-words: For example,I never know where I should park ; My desire to become a nurse is why I study so hard ; Checkmate is when your opponents kingcannot escape.


Appendix B (p. 1 of 3). Portions of transcripts recorded from children, adolescents, and adults, speaking inconversational and expository genres (MLTU = mean length of T-unit, IC = independent clause, RC = relative clause,AVC = adverbial clause, NOM = nominal clause, FRG = fragment).

Each type of clause is coded immediately after the main verb. If a clause contains more than one main verb, the clause code occurs after the first mainverb. MLTU is based on the complete sample.

Speaker 1: Boy, Age 8;7

Conversation About Dogs and Stepsisters (MLTU = 6.41 Words)

Id like [IC] a dog.Well I just like [IC] them.My grandpa has [IC] one.My dad used [IC] to have one.And my other grandpa had [IC] one.I have [IC] some stepsisters.Ones [IC] thirteen.Anothers [IC] like seventeen.Anothers [IC] twenty.Anothers [IC] thirty-four.

Explanation of Poker (MLTU = 8.49 Words)

So probably the most difficult rule about poker is [IC] trying to figure out how much you should bet [NOM].You have [IC] to decide whether your hands [NOM] good enough to bet.But you dont know [IC] what his hand is [NOM].So you have [IC] to guess what his hand is [NOM].The highest thing you can get [RC] in poker is [IC] a royal flush.Everybody I know [RC] that plays [RC] poker has never gotten [IC] a royal flush.Royal flushes are [IC] probably the hardest thing to get and the best.Nothing can beat [IC] a royal flush.If the other guy decides [AVC] to play a royal flush and you have [AVC] a royal flush with a pair of aces, youre gonna win [IC].I got [IC] a plain old flush once.

Speaker 2: Girl, Age 10;9

Conversation About Sister (MLTU = 7.38 Words)

Im [IC] used to being patient.My newest sister Katie shes learning [IC] to crawl and stand up.And she crawls [IC] into my room.I have [IC] to keep all my stuff put away.My small stuff [FRG].Or Katie will lose [IC] it.Sometimes shell try [IC] to eat it.And thats [IC] bad because my bookshelf.One shelf is [IC] this high.And one shelf is [IC] that high.

Explanation of Chess (MLTU = 8.77 Words)

The object of the game is [IC] to get the other opponents king.If the bishop was [AVC] right here and the king was [AVC] right here, that would be [IC] check.And if the rook was [AVC] right here, it would be [IC] check.And if the other rook was [AVC] right here, it would be [IC] checkmate.And if you could go [AVC] here because you couldnt go [AVC] there, its [IC] checkmate.In check, youre only going [IC] to be checked one way.They can get [IC] your king one way.But in mate, they can get [IC] them everyway.And then if one of your pawns gets [AVC] all the way back, you get [IC] another queen.But you dont want [IC] to get a queen if the other persons queen is [AVC] right there.



Speaker 3: Adolescent Boy, Age 14;2

Conversation About Halloween and Sisters (MLTU = 6.26 Words)

We went [IC] door to door.And we got [IC] candy.And we just walked [IC] around.I just threw [IC] a clown thing on.Then I went [IC].I didnt dress [IC] up.I have [IC] two sisters.My oldest sisters [IC] fifteen.Her names [IC] Terry.And my younger sisters [IC] eleven.

Explanation of Baseball (MLTU = 9.96 Words)

Theres [IC] nine people on the field.Theres [IC] a pitcher, first baseman, a second baseman, a third baseman, a short stop which stands [RC] between third and second, the catcher.And theres [IC] a left fielder, a right fielder, and center field.You go [IC] up to bat.And you get [IC] however many pitches.But if you swing [AVC] at three of them and you miss [AVC] them, then youre [IC] out.And strike is [IC] when it goes [NOM] down the middle and you could have swung [NOM] but you didnt [NOM].A ball is [IC] when it didnt go [NOM] over the plate and you hit [NOM] the ball.And a home run is [IC] when you hit [NOM] it over the fence or you hit [NOM] it and you make [NOM]

it all the way around the bases without stopping.A grand slam is [IC] when the bases are [NOM] loaded and someone hits [NOM] a home run and everyone goes [NOM] in.

Speaker 4: Adolescent Girl, Age 17;11

Conversation About School (MLTU = 10.19 Words)

I play [IC] five different musical instruments.I play [IC] the flute, the oboe, the piccolo, the keyboard, and the piano.I was [IC] part of the band.But I had [IC] to take some required classes this term.So I chose [IC] an independent study class where Im teaching [NOM] myself how to play the piano and the keyboard.And Ive been [IC] in band since fourth grade.So I just picked [IC] up instruments.And when I got [AVC] bored with one, I went [IC] to another.Im going [IC] to be a music teacher or a business teacher.My freshman year I had [IC] to take accounting or keyboarding as an elective class.

Explanation of the Shot Put (MLTU = 13.62 Words)

And you can do [IC] whats [NOM] called the standing throw half spin or a full spin hop in the ring.And the standing throw is [IC] you go [NOM] up to the board.And if youre [AVC] left handed, you usually face [IC] east.And if youre [AVC] right handed, you face [IC] west and put the ball up to about the center of your neck and curve your arm out.And you just bend [IC] down and throw the ball out as far as you can [AVC].And if you do [AVC] a half spin, what you do [NOM] is [IC] you put [NOM] whatever foot youre [RC] dominated with, which is [RC]

whatever foot you usually start walking [RC] with, up against the board point where youre going [RC] to land in the ring,which is [RC] a 20 foot mark, a 30 foot mark, and 40 foot mark, a 50 foot mark.

You point [IC] to yourself where you think [NOM] youre going [NOM] to go just to give yourself a place to land.You put [IC] your other foot that you dont have [RC] against the boards back.And you spin [IC] around.And you have [IC] to fall off your spin as you come [AVC] around and face the field.


Speaker 5: Man, Age 26;5

Conversation About Dogs (MLTU = 8.70 Words)

Im [IC] married.And I have [IC] three dogs.Theyre [IC] my family.We have [IC] two Jack Russell terriers, one yellow lab.Two boys are [IC] the terriers.And one girls [IC] the lab.And I like [IC] our dogs a lot.Theyre [IC] kind of like our children.And we train [IC] our dogs a little bit of obedience, which is [AVC] fun.You can compete [IC] if you would like [AVC] to.

Explanation of Cross-Country Running (MLTU = 11.81 Words)

When I was [AVC] in high school, we were taught [IC] some different strategies as far as racing tacticsthat we could use [RC] to fool your opponent, tire them out more quickly.

A couple of different things that I used [RC] to do was [IC] a lot of surging, which involves [RC] you racing along.And then youll run [IC] harder for a short period of time or a burst of speed over a short period of time.And you do [IC] it maybe five or six times throughout the race, different lengths and different bursts,

and just try to tire out your opponent so you can break [AVC] away from them and win the race.Another tactic is [IC] when you have [AVC] a lot of corners in a race and you can turn [AVC]

a corner and not be seen by your opponent, put [NOM] in a surge.So when your opponent comes [AVC] around the corner, youre [IC] farther ahead than you were [NOM] before.And thats [IC] a mental tactic because it tends [AVC] to make them want to give up.Thats [IC] one of my favorites.Other people that have [RC] good sprint speed will just hang [IC] on whomever until the last half to quarter mile.And then theyll just use [IC] their superior foot speed to take off and win.

Speaker 6: Man, Age 40;8

Conversation About Cat (MLTU = 9.38 Words)

Its [IC] a pretty mellow cat.Its [IC] like my family.Pretty mellow for the most part [FRG].My daughter begged [IC] me.And we had [IC] to go to the pound and get a cat.And they had [IC] to pick her out.Shes [IC] a pretty cat.She really fits [IC] with the family well.No, I went [IC] with my family.We all lounged [IC] around with the pets.

Explanation of Basketball (MLTU = 12.18 Words)

One strategy could be [IC] that you try [NOM] to advance the ball very quickly before the other team can get [AVC] back and cover and play defense.That would be [IC] called a fast break.So if one team tried [AVC] to score a goal, the offense tried [AVC] to score a goal, but they missed [AVC],

and the defensive team rebounded [AVC] the basketball, or got the basketball, then they would advance [IC] the ball as quicklyas possible down the court so that they could try [AVC] to score before the other team got [AVC] back to defend their goal.

That would be [IC] called a fast break.So thats [IC] one strategy.Some teams play [IC] really fast.Another strategy is [IC] opposite of that where teams like [NOM] to control the basketball so that they play [AVC] a much more physical game in that way.And the score is [IC] lower.But they try [IC] to control the basketball by keeping it in their possession for a long time before they score [AVC] a goal.Well, they have [IC] to be able to move up and down the court very quickly.



nippold, m. et al (2005) conversational versus expository

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