Answer:
A modal or a modal auxiliary is a word such as 'can' or 'would' which is used with a main verb to express ideas such as possibility, intention, or necessity.
Can
- ability, doubt, astonishment, permission, polite request
Example sentence: I can jump.
Could
- possibility, past ability, and to make suggestions and requests
Example sentence: We could go to the cinema tomorrow.
May
- permission, if not prohibition, supposition with doubt
Example sentence: They may be coming to our house tomorrow.
Might
- express possibility, make suggestion
Example sentence: It might rain on Friday.
Must
- to express obligation, give orders and give advice
Example sentence: You must come and visit us while you are in London!
Should
- give advice, make recommendations, talk about obligation
Example sentence: You should tell him.
Shall
Example sentence: If it's dry, shall we play outside?
Will
- wish, desire, will, confidence, in the future
Example sentence: I will give you a gift.
Would
- wish (with “to like”), polite request, a habit of the past
Example sentence: I would play the tennis when I was a child.
