13.My parents live in a small village. They always keep candles in the house ____ there is a power cut.

A. if　　 B. unless　　 C. in case　 D. so that

12. --- An ant has two stomachs --- one for itself, one for others.

　--- Really? Quite interesting. I ____ anything about it.

A. don’t know　　 B. have known　　　 C. haven’t known　　 D. didn’t know

11. I’m sorry, sir, I _____ the work last Monday, but I was too busy.

A. ought to　 B. should finish　 C. must have finished　 D. was to have finished

10. Water can absorb and give off a lot of heat without big changes in temperature, thus creating a　 _________ environment.

A. peaceful　　　　　　　 B. sensitive　　　　　　　　　 C. common　　　　　　　　　 D. stable

9.Seeing the happy _____ of children playing in the park, I’m full of joy and confidence in the future of our country.

A. sight　　　　 B. scene　　　　 C. view　　　　 D. sign

8. --- I’m worried about the coming test and I’m afraid I can’t pass it.

　--- __________! I’m sure you’ll make it.

A. Go ahead　　　 B. Good luck　　　　 C. No problem　　 D. Cheer up

7.Judging from his facial ______, he must have known the disappointing result.

　 A. impression　　 B. description　　 C. association　 D. expression

6. My mother went to the market just now and bought________ the oranges from Australia .

A. several dozens　 B. several dozen　 C. several dozens of　 D. several dozen of

5. By law, when one makes a large purchase, he should have _______ opportunity to change his mind.

A. accurate　　　 B. adequate　　　 C. urgent　　　 D. excessive

4.--- Excuse me, are you going to buy ________book?

--- Well. I need it for my next class，but it’s too expensive.

A. a　　　　　　　　 B. one　　　　 C. /　　　　 D. the