Learn English Grammar

All the auxiliary verbs except be, do and have are called modals. Unlike other auxiliary verbs modals only exist in their helping form; they cannot act alone as the main verb in a sentence.

Be, do, and have also differ from the other auxiliaries in that they can also serve as ordinary verbs in a given sentence.

The modal verbs are:-

CAN / COULD / MAY / MIGHT / MUST / OUGHT TO / SHALL / SHOULD / WILL / WOULD

Contextual classes

Modal Verb Example Uses

Can

They can control their own budgets.

We can’t fix it.

Can I smoke here?

Can you help me?
Ability / Possibility

Inability / Impossibility

Asking for permission

Request

Could

Could I borrow your dictionary?

Could you say that again more slowly?

We could try to fix it ourselves.

I think we could go to war again.

He gave up his old job so he could work for us.
Asking for permission.

Request

Suggestion

Future possibility

Ability in the past

May

May I have another cup of coffee?

China may become a major economic power.
Asking for permission

Future possibility

Might

We'd better phone tomorrow, they might be eating their dinner now.

You never know, they might give us a 10% discount.
Present possibility

Future possibility

Must

We must say good-bye now.

They mustn’t disrupt the work more than necessary.
Necessity / Obligation

Prohibition

Ought to

We ought to employ a professional writer.
Saying what’s right or correct.

Shall

(More common
in the UK
than the US)
Shall I help you with your luggage?

Shall we say 2.30 then?

Shall I do that or will you?
Offer

Suggestion

Asking what to do

Should

We should sort out this problem at once.

I think we should check everything again.

You should check your posture when using the computer.

Profits should increase next year.
Saying what’s right or correct

Recommending action

Giving advice

Uncertain prediction

Will

I can’t see any taxis so I’ll walk.

I'll do that for you if you like.

I’ll get back to you first thing on Monday.

Profits will increase next year.
Instant decisions

Offer

Promise

Certain prediction

Would

Would you mind if I brought a colleague with me?

Would you pass the salt please?

Would you mind waiting a moment?

"Would three o`clock suit you?" - "That’d be fine."

Would you like to play golf this Friday?

"Would you prefer tea or coffee?" - "I’d like tea please."
Asking for permission

Making a Request

Making a Request

Making arrangements

Invitation

Stating Preferences
! Be careful when using the modal verb "must" when giving advice. You could use "If I were you I would..." instead.