1) He may have dinner now and then play in the yard.
2) Peter can do sums very well. Can he help us?
3) — Can we play in the room? — No, you may not.
4) She cannot open this window. It is very large.
5) — Can I see Vera now? — No, you can't. She is not in.
6) — Can I help you? — Yes, you may. — Can you wash the plates? — Certainly, I can.