MODAL AUXILIARY VERBS
The modal auxiliary verbs are: CAN, COULD, MAY, MIGHT, MUST, SHOULD,
OUGHT TO, WOULD, WILL, SHALL, etc
We use Modal Verbs to talk about, for example, possibility, willingness, ability,
obligation, certainty, permission, prohibition and to offer to do something.
- Modal verbs take the same form in all persons. There is no -s ending in the third
Person singular: -She can swim.
- Modal verbs are followed by an infinitive without to (except ought to: -We ought to
go now)
- We form the negative by putting n't/not after the modal verb: -She can't swim.
And we form the interrogative by placing the same modal verb at the beginning of the
sentence: - Can she swim?
A. CERTAINTY, POSSIBILITY, WEAK POSSIBILITY,
IMPOSSIBILITY.
1. DEDUCTION: CERTAINTY& IMPOSSIBILITY:
Verbs used: MUST, CAN'T. (95%)
a) We use MUST in deductions to say that we are sure about something:
- You must be hungry. You haven't eaten all day.
- You must be tired. You have been walking all day.
- It's ten o'clock, Judy must be at the office now.
b) IMPOSSIBILITY: We use CAN'T as the negative of MUST in this meaning. In
deductions to say that something is impossible:
- That can't be John, he's in Dublin.
- He can't be at his mother's house. I've just phoned there.
c) We use MUST/CAN'T+HAVE+PAST PARTICIPLE for deductions about the
past:
-Those shoes you bought are very nice. They must have been expensive.
-You can't have been at the swimming pool yesterday!
It was closed all day yesterday!
2. POSSIBILITY: Verbs used: MAY (MAY NOT), COULD. (50%)
-To talk about present or future possibility:
- We may buy a new house soon.
- The water may not be hot enough to swim.
- It could be my mother ringing.
