----- Is that Mr. Smith?
----- It ______ be him, because he has gone to Beijing.
A. must B. should C. can’t
— Must I return the book tomorrow?
— No, you ________. You can keep it for three days.
| A．mustn’t | B．needn’t | C．can’t | D．may not |
Three fourths of the ________ in the country have run out.
| A．water | B．book | C．forests | D．news |
I don’t know _________ the problem.
| A．how deal with | B．how to deal with |
| C．what to deal with | D．what do with |
Hainan is a very good island. It’s the second ________ island in China.
| A．largest | B．large | C．larger | D．most large |
The accident happened ________ a cold winter morning.
| A．in | B．at | C．of | D．on |