Might is usually followed by an infinitive without 'to': I might change my mind. Sometimes might is used without a following infinitive: I don't think we'll need any more help, but we might.
Might does not change its form, so the third person singular form does not end in '-s': She might be late.
Questions and negatives are formed without 'do': Might I make a suggestion? ♦ Your plan might not work. The negative short form mightn't can also be used.
Might has no participles and no infinitive form.
There is no past tense but might have, followed by a past participle, is used for talking about past possibilities: The explosion might have been caused by a gas leak.
When indirect speech is introduced by a verb in the past tense, might can be used as the past tense of may: She said that she might go and stay with her mother.
There is no future tense, but might is used for talking about future possibilities: It might rain tomorrow.