19．______ walk is expected to last all day, so bring______ packed lunch.

A．A; a　 B．The; 不填　 C．The ; a　 D．A ; 不填

18. John was dismissed last week because of his ______ attitude towards his job.

A. informal　　　　　　 B. casual　　　　　　　　 C. determined　　　　　 D. earnest

17._____ we were worried about was _______ they could manage to control the pollution.

A. That; how　 B. That; whether　　 C. What; that　 D. What; whether

16. The Town Hall ______ in the 1800’s was the most distinguished building at that time.

A. to be completed　 B. having been completed　 C. completed　　　　 D. being completed

15. I was surprised at her words, which made me recognize ______.

A. what silly mistakes I had made　 B. what silly mistakes had I made

C. how silly mistakes had I made　　 D. how silly mistakes I had made

14. With the help of high technology, more and more new substances(物质) ______ in the past years.

A. discovered　　　　　　　　　　　　　　　　　　　　 B. have discovered

C. had been discovered　　　　　　　　　　　　　 D. have been discovered

13. --- Guess what! I have got an A for my term paper.

--- Great! You ______ read widely and put a lot of work into it.

A. must　　　　　　　　　 B. should　　　　　　　　 C. must have　　　　　　 D. should have

12. Alan is a careful driver, but he drives ______ of my friends.

A. more carefully　　 B. the most carefully　 C. less carefully　　 D. the least carefully

11. Leaves are found on all kinds of trees, but they differ greatly _______each other _____ size and shape.

A. from; on　　　　　　 B. from; in　　　　　　　 C. by; in　　　　　　　　　 D. in ;from

10. Between the two generations, it is often not their age, _________ their education ______ causes misunderstanding.

A. like; which　　　　 B. as ; that　 　　　　C. or; what　　　　　 D. but ; that