18. There was such a long queue for coffee in　 the intervals that we ____ gave up.

A. eventually　 B. unfortunately 　　C. generously 　　D. purposefully

17. He insisted that he _____ really very tired and that he　 ____　to have a rest.

A. was; be allowed 　　　　　　B. was; must be allowed

C. should be; must be allowed 　D. should be; be allowed.

16. When he left for the sea, he ______ nothing but some food and water.

A. took along 　B. brought on 　　C. took down 　　D. brought up

15. I won’t tell the student the answer to the math problem until he ______ on it for more than an hour.

A. has been working　 　B. will have worked 　C. will have been working 　D. had worked

14. So far scientists ______　13 vitamins that play vital roles in regulating the chemical reaction.

A. identifies　 　B. have identified　 C. have been identified 　D. have been identifying

13. Improving the environment needs a lot of money, but a good environment can , _____　promote a city’s appearance and competition.

A. in return　 B. in turn　 C. in favor　　 D. in need

12. The manager, ______ it clear to us that he didn’t agree with us, left the meeting room.

A. who has made　 B. having made　 　C. made 　D. making

11. They had a pleasant chat ____ a cup of coffee.

A. for　 　B. with 　C. during 　D. over

10. It is suggested that we _____ the design of the machine before May Day.

A. should finish　 B. have finished　 C. will finish D. should have finished

9. I don’t agree with what he said. I think the theory is true ______ all cases.

A. of 　　B. at 　　C. about 　D. over