Modal verbs and other expressions

Present & Future

Past

Other expressions

Obligation

must

have (got) to

should

ought to

had to

should have done

ought to have

had better (not)

to be to

No obligation

do not have to

did not have to

Giving advice

should

ought to

can

could

should have

ought to have

could have done

Complaining

You could

You should

shouldn’t have

ought to have

might have

Giving orders

must

ought to/should (not)

could

should (not) have

ought (not) to have

had better (not)

Asking for advice

Shall I…?

Should I….?

Would you….. if ….?

Necessity

must

have to

need

need to

had to

needed

needed to

No necessity

don’t have to

needn’t

don’t need to

didn’t have to

needn’t have

didn’t need to

Ability

can

be able to

could

were able to

was able to

be capable of

be good at

be bad at

manage to

succeed in

No ability

can’t (cannot)

be not able to

couldn’t

wasn’t able to

weren’t able to

Permission

can

could

may

could

be allowed to

be permitted to

let

be forbidden to

be banned from

be prohibited from

prohibition

cannot

can’t

may not

mustn’t

couldn’t

Making requests

Can I …?

Could I …?

May I …..?

Would you mind ….?

Will you …..?

Certainty

(positive)

must

must have done

be bound to

Certainty

(negative)

can’t

couldn’t

can’t have done

couldn’t have done

Possibility

may

might

could​​ 

may have done

might have done

could have done

can’t have done

Expectation

ought to​​ 

should​​ 

ought to have done

should have done

No possibility

may not

might not

may not have done

might not have done

Probability

will

should

ought to

Making offers

Shall we

Can I

I can

I could

I will

Would you like

could have

would have

Why don’t I …?

Why didn’t I …?

Making suggestions

Shall we/I

We can

We could

could have

should have

Why don’t we

Let’s

How about

What about