--- Listen! David is talking happily with his mother in the next room.
--- It ______ be his mother. She has gone to Yunnan to be a volunteer doctor.
| A．should | B．must |
| C．can’t | D．mustn’t |
— Must I finish my homework now?
— No, you ________. You can go home now.
| A．needn’t | B．mustn’t |
| C．shouldn’t | D．can’t |
-- Must I return the book this week?
-- No, you ______. You can _____ it for 20 days.
| A．mustn’t; keep | B．don’t have to; borrow |
| C．needn’t; keep | D．mustn’t; lend |
I like this room. You ______ see the mountains from the window.
| A．can | B．should | C．must | D．need |
I'm very glad I have my own room in my house. I ______ do what I want in it.
| A．must | B．have to |
| C．need | D．can |