Use of May and Might

May
• It is used to indicate possibility:-
(1) It may rain tonight.
(2) It may hail today.
(3) It may snow today.
(4) I may come to see you in the evening.
(5) It may sleet tomorrow.

• It is used to indicate permission:-
(1) May I borrow your bicycle for a day?
(2) May I go to the toilet, sir?
(3) May I go home now?
(4) May I wait for him?
(5) May I come in, madam?

• It is used to indicate a purpose:-
(1) We eat so that we may live.
(2) We earn so that we may spend.
(3) He works hard so that he may get through.
(4) He runs fast so that he may catch the bus.
(5) He speaks aloud so that he may be heard by the audience.

Note that conjunction 'so that' is always followed by may + Ist form of verb in the present tense. Never use 'can' or any other modal verb.

• It is used to indicate a hope or wish:-
(1) May God grant you speedy recovery!
(2) May God bless you!
(3) May you scale great heights in life!
(4) May God grant you all the riches of the world!
(5) May you top the list of successful candidates!

Note that the sentences expressing wish or prayer also start with 'may'. But each of these sentences ends with a mark of exclamation (!).

Might
• It is used to indicate a purpose in the past tense:-
(1) He worked hard so that he might pass the examination.
(2) He ran fast so that he might catch the bus.
(3) He spoke aloud so that he might be heard by the audience.
(4) He earned so that he might spend.
(5) He flattered his boss so that he might be promoted.

Note that conjunction 'so that'
is always followed by might + Ist form of verb in the past tense. Never used 'could' or any other model verb.

• It is used to indicate a lesser possibility:-
(1) It might sleet in the evening.
(2) It might snow tonight.
(3) It might rain today.
(4) It might hail in the afternoon.
(5) It might blow heavily tomorrow.

• It is used as the past tense of 'may':-
(1) The teacher told the students that he might not come next day.
(2) He said that he might come next day.
(3) He told me that he might meet me on Tuesday.
(4) He threatened me that he might reveal the secret to the police.
(5) He informed me that he might give me some money next day.

• It is used to ask permission politely:-
(1) Might I use your mobile phone?
(2) Might I use you pen?
(3) Might I sit down?
(4) Might I know who you are?
(5) Might I go home now?