can to ask somebody to do something
to ask for or give permission
to offer to do something
Can you help me?
Can I have another chocolate?
Yes, you can use my laptop.
No, you you can't use my laptop.
Can I help you with your bags?
Could you call me a taxi?
Could I come to work a little later?
Do you think I could borrow your phone?
may to ask for or give permission
(polite)
May I speak to you for a second?
Yes, you may use my laptop.
No, you may not use my laptop.
would you like to make an offer or invitation Would you like another chocolate?
Would you like to go out?
will to ask somebody to do something Peter, will you come here for a minute?
would to ask somebody to do something
(very polite)
Would you carry my bags for me,
please?
shall I ... to offer to do something Shall I answer the phone for you?