MODALS PART 2

1. Expressing degress of certainty present time

Examples:

Why isn't John is class?

100% sure: He is sick.

95% sure: He must be sick.

Less than 50% sure:

He may be sick.

He might be sick.

He could be sick.

"Degree of certainty" refers to how sure we are--what we think the chances are--that

something is true.

If we are sure something is true in the present, we don't need to use a modal. For examples, if

I say, "John is sick," I am sure; I am stating a fact that I am sure is true. My degree of

certainty is 100%.

--Why isn't John in class?

(a) He must be sick. (Usually he is in class every day, but when I saw him last night, he

wasn't feeling good. So my best guess is that he is sick today. I can't think of another

possibility.

Must is used to express a strong degree of certainty about a present situation, but the degree

of certainty is still less than 100%.

In (a) The speaker is saying: "Probably John is sick. I have evidence to make me believe that

he is sick. That is my logical conclusion, but I do not know for certain.

Why isn't John in class?

(b) He may be sick.

(c) He might be sick.

(d) He could be sick. (I don't really know. He may be at home watching TV. He might be at

the library. He could be out of town.)

May, might and could are used to express a weak degree of certainty.

In (b), (c), and (d): The speaker is saying: "Perhaps, maybe, possibly John is sick. I am only

making a guess. I can think of other possibilities.

(b), (c) and (d) have the same meaning.

Maybe  (spelled as one word) is an adverb. Maybe he is sick. 

May be (spelled as two words) is a verb form: He may be sick.

2. Degrees of certainty: Present time negative

Examples:

100% sure: Sam isn't hungry.

99% sure: Sam couldn't be hungry.

99% sure: Sam can't be hungry.

95% sure: Sam must not be hungry.

Less than 50% sure:

Sam may not be hungry.

Sam might not be hungry.

(a) Sam doesn't want anything to eat. He isn't hungry. He told me his stomach is full. He says

he isn't hungry. I believe him.

In (a): The speaker is sure that Sam is not hungry.

(b) Sam couldn't be hungry.! That's impossible! I just saw him eat a huge meal. He has

already eaten enough to fill two grown men. Did he really say he'd like something to eat? I

don't believe it.

In (b): The speaker believes that there is no possibility that Sam is hungry (but the speaker is

not 100% sure). Notice the negative use:

couldn't and can't forcefully express the idea that the speaker believes something is

impossible.

(c) Sam isn't eating his food. He must not be hungry. That's the only reason I can think of.

In (c): The speaker is expressing a logical conclusion, a "best guess."

(d) I don't know why Sam isn't eating his food. He may/might not be hungry right now. Or

maybe he doesn't feel well. Or perhaps he ate just before he got here. Who knows?

In (d): The speaker uses may not/might not to mention a possibility.

3. Degrees of certainty in the future

Notice that future certainty and present certainty are very similiar.

If you are very confident then use will (future)

The party will be great.

If you are mostly certain then use should or ought to.

The party should be great.

The party ought to be great.

If you are around 50% certain use may.

The party may be great.

If you are not very sure at all use might or could. These show that you doubt it.

The party might be great.

The party could be great.

Modals of Certainty in the Present - Exercise 1

Choose the correct modal to complete the sentence.

1. George ordered a large hamburger with everything on it except mustard. He

_______________ like mustard.

a. may not

b. mightn't

c. isn't

d. does not

2. Alex wanted to get the promotion very much, but he didn't. He

_____________________ disappointed

a. could be

b. maybe

c. must be

d. might be

3. Sam is usually very friendly, but he hasn't smiled at all today. He ______________

worried about something.

a. is

b. must be

c. might be

d. might have been

4. You just ate five large slices of pizza, two pieces of chocolate cake and some ice

cream. You ______________ still be hungry.

a. mustn't

b. couldn't

c. can't

d. must

5. I don't know why Stephanie isn't eating with us. She _____________ hungry.

a. might not be

b. couldn't be

c. might be

d. isn't

6. I wonder why Mary and Fred are late. They ___________ know how to get here.

a. might not

b. maybe not

c. aren't

d. don't

7. Bob usually drives his car to work, but today he got on the bus. Something

_______________ wrong with his car.

a. couldn't be

b. must be

c. is

d. might be

8. Glen's wife is Japanese. There is a picture of a Japanese woman on his desk. That

____________ his wife.

a. must be

b. could be

c. might be

d. is

9. You went to bed at 9:30 last night and got up at 11:00 this morning. You

_________________ still be tired.

a. can't

b. couldn't be

c. might

d. must

10. Tom is wearing a Vancouver Canucks T-shirt. He ______________ a Canucks fan.

a. must be

b. can't be

c. is

d. maybe

Building blocks Modals of Possibility and Probability with Continuous Tenses

We use modals of possibility or probability to make a guess or draw a logical conclusion

about an activity in progress at the present time; that is, during the time of speaking.

Formula: SUBJECT + APPROPRIATE MODAL + BE + ING VERB

Person A: What’s all that noise?

Person B: The neighbour’s son is in a rock band. They must be practicing.

We also use modals of possibility or probability to make guesses or logical conclusions about

past activities.

Formula: SUBJECT + APPROPRIATE MODAL + HAVE BEEN + ING VERB

Person A: I didn’t hear a sound when I passed by the children’s room earlier.

Person B: They must have been sleeping.

Must, could, might, may, couldn’t, can’t, may not and might not are used to show how certain

the speaker is that an action is presently occurring or not occurring. Using must conveys a

strong feeling of certainty; nevertheless, there is still some doubt in the speaker’s mind.

Could, may and might show that a speaker is 50% or less certain that an action is in progress.

Couldn’t and can’t show that the speaker believes strongly that a situation is not taking place.

For example:

It’s noon. George went to bed at 10:00 last night. He can’t still be sleeping!

May not and might not convey the idea that a speaker is 50% or less certain that an action is

not possible or probable. They are not normally used in their contracted forms.

Correct: They aren’t here yet and it’s getting late. They might not be coming.

Incorrect: They aren’t here yet, and it’s getting late. They mightn’t be coming.

Might and could are used in questions regarding the possibility or probability of actions

taking place. However, may and must are not.

Correct: Could Tom be studying now?

Incorrect: May Tom be studying now?

For most short answers, a modal alone is used. However, if the question includes a be verb, a

modal with be is required.

Person A: Is Simon joining us?

Person B: I’m not sure. He might be.

Remember that not all verbs are used in the continuous (progressive) form. Non-action verbs

that describe situations or conditions that aren’t expected to change, such as seem, appear,

cost, weigh, have and be are not used. Other types of non-continuous verbs are:

Verbs of the senses (hear, smell, see, taste, etc.)

Verbs of ownership (have, belong, own, possess)

Verbs that convey feelings (love, hate, like, hate, prefer, want, etc.)

1) I can't find my wallet. I ________________________________________________

a. May I leave it at home?

b. I left it at home.

c. I may have left it at home.

d. I am leaving it at home.

2) Although it's sunny and dry now, I see several people carrying umbrellas. It

____________________________________________________

a. can't have been raining earlier.

b. must have been raining earlier.

c. rained earlier.

d. might have been raining earlier.

3) James and Betty went to Hawaii on Friday for a two week vacation. Right now, they

_____________________________________

a. must be relaxing on a sunny beach.

b. are relaxing on a sunny beach.

c. might relax on a sunny beach.

d. might be relaxing on a sunny beach.

4) PERSON A: The children are very quiet. I wonder what they are up to?

PERSON B: I don't know. They __________________________________________

a. will have been sleeping.

b. could be sleeping.

c. could have been sleeping.

d. are sleeping.

5) PERSON A: Where's Danny?

PERSON B: I don't know. He has an important exam tomorrow, so he

_________________________________________________

a. can't be studying.

b. must be studying.

c. is studying.

d. studied.

6) I wanted to talk to the professor about my grade, but he wasn't in his office. I guess he

____________________________________________

a. was teaching another class.

b. might have been teaching another class.

c. must have taught another class.

d. might be teaching another class.

7) ____________________________ a call for you. You should check the answering

machine just in case.

a. There might have being

b. There must have been

c. There might have been

d. There was

8) PERSON A: I was raised in a large city.

PERSON B: That _________________________________________

a. must be interesting.

b. may have been interesting.

c. must have to be interesting.

d. must have been interesting.

9) Bob's teenage daughter always wears pink clothing. She even painted her bedroom

pink. She __________________________________

a. must like pink.

b. might be liking pink.

c. must to like pink.

d. might like pink.

10) PERSON A: Many people were laughing throughout the movie.

PERSON B: It __________________________________________

a. could have been very funny.

b. must have been very funny.

c. was funny.

d. maybe funny.

Can and Could for Ability

 General Abilities

Some abilities are general: you have the skill to do it at any time you like.

I can play the accordion.

I could play the violin when I was a child.

Remember: modal verbs don't need an 's' for he/she/it, and always have an infinitive

verb (without 'to') after them.

Incorect :He cans play the piano.

Corect :He can play the piano.

Incorect :They can to make delicious cakes.

Corect :They can make delicious cakes.

General Abilities

Present

+ I can speak 3 languages.

- I can't speak Arabic.

? Can you speak any languages?

Past

+ I could speak some German when I was 15.

- I couldn't speak any Spanish when I was 15.

? Could you speak French when you were 15?

Note: if you want to talk about abilities in the future, or use other tenses, you need to

use be able to.

I will be able to speak perfect French one day.

I have been able to swim since I was a child.

Specific Abilities in the Past

Not all abilities are general. Some abilities happen only once (or a certain number of

times) in a particular situation. In positive sentences, we only use was able to.

I was very tired but I could stay awake all night. X

I was very tired but I was able to stay awake all night. ✓If the sentence is negative, we use could or was able to.

I couldn't hear him because of the music. ✓I wasn't able to hear him because of the music. ✓

SUMMARY CHART OF MODALS AND SIMILAR EXPRESSION

AUXILIARY USES PRESENT/FUTURE PAST

May (1) polite request May I borrow your pen?

(2)formal permission You may leave the room.

(3) less than 50%

certainty

Where is John?

He may be at the library.

He may have been at

the library.

Might (1) Less than 50%

certainty

Where is John?

He might be at the

library.

He might have been

at the library.

(2) polite request (rare) Might I borrow your

pen?

Should (1) advisability I should study tonight. I should have studied

last night.

(2) 90% certainty You should do well on

the test.(future only,  not

present)

She should have

done well on the test.

Ought to (1) advisability I ought to study tonight. I ought to have

studied last night.

(2) 90% certainty She ought to do well on

the test. (future only, not

present)

She ought to have

done well on the test.

Head better (1) advisability with

threat of bad result

You had better be on

time, or we will leave

without you.

(past form

uncommon)

Be supposed

to

(1) expectation Class is supposed to

begin at 10

Class was supposed

to begin at 10.

Be to (1) Strong expectation  You are to be here at

9:00.

You were to be here

at 9:00.

Must (1) Strong necessity I must go to class today. I had to go to class

yesterday.

(2) prohibition

(negative)

You must not open that

door.

(3) 95% certainty Mary isn’t in class. She

must be sick. (Present

only)

Mary must have been

sick yesterday.

Have to (1)Necessity I have to go to class

today.

I had to go to class

yesterday.

(2)Lack of necessity

(negative)

I don’t have to go to

class today.

I didn’t have to go to

class yesterday.

Have got to (1) necessity  I have to go to class

today.

I had to go to class

yesterday.

Will (1) 100% certainty He will be here at 6:00.

(future only)

(2) willingness The phone is ringing. I’ll

get it.

(3) Polite request Will you please pass the

salt?

Be going to (1) 100% certainty He is going to be here at

6:00. (future only)

(2) definite plan I’m going to paint my

bedroom. (future only)

I was going to paint

my room, but I didn’t

have time.

Can (1) ability/possibility I can run fast. I could run fast when

I was a child, but now

I can’t.

(2) informal permission You can use my car

tomorrow.

(3) informal polite

request

Can I borrow your pen?

(4) impossibility

(negative only)

That can’t be true! That can’t have been

true!

Could (1) past ability I could run fast when

I was a child.

(2) polite request Could I borrow your

pen?

Could you help me?

(3) suggestion I need help in math.

You could talk to your

teacher.

You could have

talked to your

teacher.

(4) less than 50%

certainty

Where’s John?

He could be at home.

He could have been

at home.

(5) impossibility

(negative only)

That couldn’t be true! That couldn’t have

been true!

Be able to (1)  ability I am able to help you. I

will be able to help you.

I was able to help

him.

Would (1) polite request Would you please pass

the salt? Would you

mind if I left early?

(2) preference I would rather go to the

park than stay home.

I would rather have

gone to the park.

(3) repeated action in

the past

When I was a child, I

would visit my

grandparents every

weekend.

Used to (1) repeated action in

the past

I used to visit my

grandparents every

weekend.

Shall (1) polite question to

make a suggestion

Shall I open the

window?

(2) future with ”I” or

“we” as subject

I shall arrive at nine.

(will = more common)

EXERCISE.

1.Before this year, I __________ move out of my parents' house because I did not

have a job.

a. may not

b. cannot

c. should not

d. could not

e. shall not

2.But now that I have finished college and have a job, I realize that living at home

_____ drive my parents and me crazy. (potentially)

a. could

b. would

c. should

d. would have

e. should have

3.Unfortunately, it's not so easy to find to find an apartment in the city. Without an

agent, you _____ not be able to find all the available listings. (possibility)

a. ought to

b. must

c. should

d. might

e. can

4.Before now, I couldn't sign a lease, but now I _____ because I am twenty-one.

a. able

b. can

c. can able

d. can do

e. sign

5.I asked my friends to help me move because I knew that I _____ fit all my

possessions into my little car. (inability)

a. can't be able to

b. not able to

c. don't be able to

d. couldn't

e. couldn't be able to

6.My best friend said, " I _____ help you move next week." (an offer)

a. able to

b. would be able to

c. be able to

d. must be able to

e. will be able to

7.He added, " I _____ help earlier in the morning than later in the afternoon."

(preference)

a. would better

b. would like

c. would have

d. would rather

e. would

8.My father also offered to help me move. He __________ be really eager to have

me move out! (conclusion)

a. must

b. will

c. can

d. ought to

e. have to

9.Another friend told me that he ______ me move, but he never showed up.

a. would help

b. would have helped

c. will help

d. would helped

e. will have helped

10.With the help of three friends, I ___ get all my possessions into the new condo.

("managed to")

a. am able to

b. can

c. could

d. was able to

e. could have

11.My parents are happy for me, but warned, "You _____ spend all your money each

month. Save a little extra money for unexpected emergencies."

a. mustn't

b. don't have to

c. must not have

d. aren't able to

e. would not

12.I know that everyone _______ save a little extra money, but it is hard with so

many bills to pay. (customary, expected behavior)

a. must

b. is supposed to

c. has to

d. was able to

e. could have

13.I made a few purchases. The first thing that I _____ was furniture. (requirement)

a. must have

b. had to have

c. must have had

d. have to have

e. would have had

14.I _____ on the wood floor, but it was too hard, so I bought a sofa-bed. (option not

taken)

a. could sleep

b. couldn't sleep

c. could have slept

d. could of slept

e. couldn't have slept

15.It _____ about a year until I am able to completely furnish my apartment.

(prediction)

a. must take

b. will take

c. would take

d. will have taken

e. must have taken

16.By this time next year, I _____ a lot about living independently. (time-relative

prediction)

a. must learn

b. will learn

c. would learn

d. will have learned