It is used to express:--
a. Possibility or probability.
b. A wish
c. A request
d. Hesitation or doubt on the part of the speaker
e. A purpose
f. A suggestion
a. He might have returned last night.
b. I hope that he might pass.
c. You might post this letter on your way to school.
d. Might I go to the fair?
e. I sent my money that he might buy the book.
f. You might consult your brother about this matter.