The Modal Verbs May and Might

The modal verb may has two tense forms: may (the Present Simple) — might (the Past Simple).

May can express the following meanings:

Permission or asking for permission (formal).
- May I interrupt you?
- You may be seated
The form might is used in indirect speech according to the rules of the sequence of tenses
- He told me that I might go home
Prohibition (formal)
- You may not smoke in here
Possibility due to circumstances like can (only in affirmative sentences with an indefinite infinitive)
- You may/can order a ticket by telephone
Uncertainty. Might is less categoric
- He may be tired
- He might come later
May or might are used with all forms of the infinitive. The Perfect Infinitive is used to refer the action to the past
- He may/might have sold the house
- They might not be working in the library now

NOTE: Supposition or uncertainty in questions is rendered by: Is he likely to…?, Is it likely that he …?, Do you think…

- Is Mary likely to arrive tonight?
Reproach, hurt feelings (only might is used)
- You might at least say you’re sorry
- You might have warned me!
Wish
- May you be happy!

Here are a few important rules for modal verbs: