Modal verbs

Modal verb "must" expresses:

• duty

• strong obligation

• prohibition

• permission

Modal verb "needn’t" expresses:

• necessity

• request

• lack of necessity

• prohibition

Modal verb "need" expresses:

• duty

• necessity

• possibility

• permission

Modal verb "don’t have to" expresses:

• lack of necessity

• lack of obligation

• permission

• strong obligation

Modal verb "have to" expresses:

• possibility

• prohibition

• strong necessity

• suggestion

Modal verb "may" expresses:

• strong advice

• permission

• possibility

• necessity

Modal verb "can" expresses:

• possibility

• suggestion

• necessity

• obligation

Modal verb "mustn’t" expresses:

• lack of necessity

• prohibition

• strong obligation

• possibility

Modal verb "could" expresses:

• ask for permission

• give permission

• strong necessity

• strong advice

Modal verb "might" expresses:

• suggestion

• request

• permission

• possibility