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IT 5 Modals to Express Degrees of Certainty

Nosy Neighbors

Nosy Neighbors 1

Honey, how can Mrs. Carson

afford a Ferrari? Isn’t she a teacher?I suppose. Or

she could have won the lottery.

Who knows? She may

have gotten a big raise at

work.

Well, she might have

inherited some money from her

family.

I doubt it. She had to have

robbed a bank!

You could be right.

Nosy Neighbors 2

I haven’t seen the

Chins for a month.They may

have been abducted by

aliens.

Or they might be staying with their son for a

while.

Well, they couldn’t

have gone on vacation. The

dog is still there.

Hmmm. They must

have moved to an exotic island.

Then they should be

very happy.

Speculating about the Present

Modals speculating about the present are followed by a base form verb.

Then they should be very happy.

base form verb

You could be right.

Speculating about the Past

Modals speculating about the past are followed by the past participle.

past participle

She could have won the lottery.

She may have gotten a big raise.

Review

Modals and modal-like expressions express degrees of certainty.

Degree of Certaintycertain

near certainty

near impossibility

less certain

no modal

musthave to have got to

can’t couldn’t

may mightcould

Certainty

Modals and modal-like expressions express degrees of certainty. Don’t use a modal for 100% certainty.

Mrs. Carson got a raise.

The Chins went on vacation.

Near Certainty

There are several modals that express near certainty, including must have and had to have.

They must have moved to an exotic island.

He had to have robbed a bank.

Near Impossibility

There are several modals that express near certainty that something is impossible, including couldn’t have and can’t.

They just moved here.

They left all the lights on!

They can’t be out of town.

They couldn’t have moved away.

Less Certainty

There are several modals that express less certainty, including may, and might.

They may have been abducted by aliens.

They might be staying with their son.

Use modals to suggest reasons for these classroom situations. Speculate on what might have happened.

Example: One of your classmates is late.

She must have gotten stuck in traffic. There was a big accident.

1. You smell smoke.

2. The teacher is angry.

3. The desks are shaking.

4. You can’t find your textbook.

5. The lights go out.

Practice 1

She ought to take us for a drive soon.

Modals speculating about the future are also followed by a base form verb. The modals should and ought to express near certainty.

That Ferrari should last a lifetime.

Speculating about the Future 1

Use may, might, and could when you are less certain.

Speculating about the Future 2

The Chins may not return.The house might get sold.They could move next month.

Use modals to express future possibilities about these present situations.

Example: We shop for food at grocery stores.“Smart” kitchens might calculate what we need and order it electronically. In the future, household computers may do all our shopping.

1. Ordinary people don’t travel in space.

2. Houses are made of wood.

3. People pay for products with cash or credit cards.4. Our fingerprints provide identification.

Practice 2