II Modality: Functions of modality

A Primary functions

• Giving advice (should, ought to, had better, you’d rather)

• Granting permission (You’re allowed to, you can do, you may)

• Expressing prohibition (mustn’t, you are not to do sth, you shalt no steal, something is banned, something prohibited, there is a ban on sth)

• Expressing necessity (duties, obligations) (must / need/ have to / be obliged to do it / be forced to do it / be compelled to do it / be under (no) obligation)

• Expressing ability (can, be able to, have the ability to / be capable of , manage)

• Expressing opportunity, freedom to do sth (can, have the possibility of doing something, have the opportunity to do sth)

B Secondary functions

• Making suppositions both about the present, the future and the past

• Making deductions

• He must be very clever. (present deduction)

• He must have been very clever when he was young but now he’s not so brilliant. (past deduction)

III Use of infinitives after modal verbs:

Present infinitives:

• He may be abroad. (simple)

• He may be staying abroad. (progressive)

• He may be employed in a travel agency. (passive)

Perfect (past) infinitives:

He may have been abroad when you phoned him. (simple)

III a selection of “easier” transformations

1 Perhaps she’s abroad.

She may be abroad.

2 Perhaps she wasn’t taking a bath.

She may not have been taking a bath.

3 Perhaps she’s been studying.

She may/might have been studying .

4 I think she has lost her senses / bearings.

She must/could have lost her senses.

5 I suppose he has left for Australia.

He must/could/may have left for A.

6 It’s certain that he’ll fail.

He is bound / certain to fail.

7 It is certain that she (has) attended the ceremony.

She is bound to have attended the ceremony.

8 I must reject this plan.

• I have no option other than rejecting this plan.

• I have no intention of accepting this plan.

• I have no choice / alternative but to reject this plan.

9 I don’t think she’ll pass the test.

• She can’t possibly pass the test.

• She’s unlikely to pass the test.

• She’s bound to fail the test.

10 It wasn’t necessary for you to buy so many roses, which you did.

You should not have bought so many roses /needn’t have bought so …. . They must have cost a fortune / the earth.

11 Was it necessary for her to behave like this?

Did she have to / need to behave like this?

12 It wasn’t necessary for me to walk to work as she gave me a lift.

I didn’t have / need to walk to work …

13 There’s no need to correct the tests today. They can wait a bit.

The tests don’t need correcting today / don’t need / have to be corrected.

14 He isn’t obliged to tell you the truth.

• He doesn’t have / need to tell you the truth.

• It isn’t necessary for him to tell you the truth.

• He’s under no obligation to tell you the truth.

• There’s no obligation for him to tell you the truth.

15 Do you have to take tests at this school?

• Are you obliged / required to take tests …

• Are tests mandatory / obligatory / necessary

16 Senior students don’t have to take tests.

• Senior Ss are under no obligation to take tests.

• Senior Ss have the option of not taking tests.

• Senior Ss are not obliged to take tests.

17 You mustn’t skip classes if you want to get a credit for the course.