Uses
What modal verb do we use to express probability?
May
Might
Could
Can
What modal verb do we use to express lack of obligation or necessity?
needn't
What modal verbs we use to express prohibition?
Mustn't
Can't
What modal verbs we use to express necessity?
Need
Must
What modal verb do we use to give advise or a suggestion?
Should
Ought to
Had better
What modal verbs we use to express improbability?
May not
Might not
What's the negative form of "ought to"?
ought not to
What's the negative form of "had better"?
had better not
Which "need" is a modal verb?
A: You don't need to finish it.
B: You needn't finish it.
B
What modal verbs do we use to express an external obligation?
Have to
(Must in formal and written English)
What modal verbs do we use to express a personal obligation?
Must
What modal verbs we use to express a positive deduction(likelihood)?
Must
What modal verbs we use to express regret about something that did not happen?
Should + have + past participle
What modal verbs we use to express a negative deduction?
Can't
What modal verbs we use to express regret about something that happened?
Should not + have + past participle