1. Modals to Express Degrees of Certainty2
Modals to Express Degrees of Certainty
Nosy Neighbors
Focus on Grammar 5
Part II, Unit 6
By Ruth Luman, Gabriele Steiner, and BJ Wells
Copyright © Pearson Education, Inc. All rights reserved.

2. Nosy Neighbors 1
Well, she might have inherited some money from her family.
Honey, how can Mrs. Carson afford a Ferrari? Isn’t she a teacher?
Who knows? She may have gotten a big raise at work.
I suppose. Or she could have won the lottery.
I doubt it. She had to have robbed a bank!
You could be right.

3. Nosy Neighbors 2
Well, they couldn’t have gone on vacation. The dog is still there.
I haven’t seen the Chins for a month.
Or they might be staying with their son for a while.
They may have been abducted by aliens.
Hmmm. They must have moved to an exotic island.
Then they should be very happy.

4. Speculating about the Present
Modals speculating about the present are followed by a base form verb.
You could be right.
base form verb
Then they should be very happy.

5. Speculating about the Past
Modals speculating about the past are followed by the past participle.
She could have won the lottery.
past
participle
She may have gotten a big raise.

6. Review Degree of Certainty
Modals and modal-like expressions express degrees of certainty.
Degree of Certainty
certain
near certainty
near impossibility
less certain
no modal
must
have to
have got to
can’t
couldn’t
may
might
could

7. Certainty The Chins went on vacation. Mrs. Carson got a raise.
Modals and modal-like expressions express degrees of certainty. Don’t use a modal for 100% certainty.
The Chins went on vacation.
Mrs. Carson got a raise.

8. Near Certainty They must have moved to an exotic island.
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.

9. Near Impossibility They couldn’t have moved away.
There are several modals that express near certainty that something is impossible, including couldn’t have and can’t.
They couldn’t have moved away.
They just moved here.
They can’t be out of town.
They left all the lights on!

10. Less Certainty They may have been abducted by aliens.
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.

11. Practice 1 Example: One of your classmates is late.
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.

12. Speculating about the Future 1
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.
She ought to take us for a drive soon.

13. Speculating about the Future 2
Use may, might, and could when you are less certain.
The Chins may not return.
The house might get sold.
They could move next month.

14. Use modals to express future possibilities about these present situations.
Practice 2
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.

15. References
Copyright © 2006 Pearson Education and its licensors. All rights reserved.