—It’s too hot. Would you mind _______ the door? —_______. Please do it now.
My mother is ill. I ______ stay at home to take care of her.
—Is Mr. Smith over there? —It ________ be him. He has gone to Beijing on business.
After a long walk, the old man be tired now.
You ________ worry about him. He will get well soon. A. needn’t B. can’t C. mustn’t
---Must I return the magazine to you right now, Sandy? ---No, you _____.You may keep it until next Wednesday.