Polite Request with "I', "You", "Would you mind", and using imperative sentence

Polite requests with “I” as the subject

May I Ex: May I (please) borrow your pen? Could I Ex: Could I borrow your pen?	Formal In a polite request, could has a present or future meaning, not a past meaning.
Can I Ex: Can I borrow your pen?	Informal

Polite requests with “You” as the subject

Would You Ex: Would you pass the salt (please)? Will You Ex: Will you (please) pass the salt?	Would you is more common and is often considered more polite.
Could You Ex: Could you pass the salt?	Formal
Can You Ex: Can you pass the salt?	Informal

Would you = do you want to do this please?

Could you = do you want to do this please, and is it possible to do this?

Polite Request with would you mind

Would you mind if I closed the window? Would you mind if i used the phone?	Would you mind if I is followed by the simple past.
Would you mind closing the window? Would you mind giving the book to Anita?	Would you mind is followed by –ing (a gerund)

Using imperative Sentences to make Polite Requests

Shut the door Be on time Don’t shut the door Don’t be late Turn right at the corner	Imperative sentence can be used to give direction and an order.
Shut the door please	It becomes a polite request when the word please added.

taken from www.allposters.com