‘May’ is a modal auxiliary.
It does not take an ‘s’ in the present tense.
The past tense or conditional is ‘might’.
You use it like an auxiliary in the interrogative and negative forms:
May I go out? no, you may not.
It has no infinitive form.
It has no participle.
If you want to use it in a tense which is not present or past you have to use ‘to be allowed to’.
‘May’ is used to express :Permission:
May I go out Mum?
You may eat some cake Jim.
He may come late.
He may be on holidays.
Suggestion or reproach with ‘might’:
He doesn’t know what to do; he might ask Wendy.
You might have done the washing-up !
May this year bring you happiness and health !
May/ might are sometimes used with a past participle :
He might have been killed !
He may have phoned while I was having a shower.
May vs Might:
1. Take your umbrella as it today.
2. He is still at work ! He late I am afraid.
3. John couldn’t repair his washing-machine; he his neighbour.
4. They talked too loudly. They the baby !
5. Darling! I wonder if I you that marvellous car you saw yesterday ?
6. Mum ! My friends are having a party tonight ; please?
7. Sweetheart ! As you were at home, you the ironing, don’t you think ?
8. Yes darling, but I was afraid I your marvellous shirt !
9. He late because his flight has been delayed.
10. Look at those clouds ! It in a minute.