完成句子。
l. That ______ (不可能) he Mary. She's in hospital.
2. — Could I borrow your dictionary?
— Yes, of course you ______ (可以).
3. — When can I come for the photos? I need them tomorrow afternoon.
— They ______ (应该) be ready by 12:00.
4. — Shall I tell John about it?
— No, you ______ (不必). I've told him already.
5. — May I pick a flower in the garden?
— No, you ______ (一定不能).