20. 　　 The gap between rural and urban education in China is widening, and education is the key 　 to _____ rural problems.

A. solving　　 　 B. solve　 　　 C. settle　 　　　　 D. settling

19. 　　 _____, he made great progress all round in the past exam.

A. Much to his delight　　 　　　　　　　 B. At his own expense

C. Once and for all　　　　　　　　　　 D. Apart from English

18. 　　 Cloned pigs differ _____ the originals _____ looks and behavior.

A. in; from　　 　　 B. from; in　 　 　　C. at; from　　 D. from; at

17. 　　 _________from other continents for millions of years, Australia has many unique plants and animals.

　 　A. To separate　　 B. Separating　　 C. Being separated　　 D. Having been separated

16. 　　 ________ hearing the news from his parents, he ________tears.

　 A. To, centered on　　 B. On, burst into　　　 C. Of, set out　　　 D. At, passed away

15. Whoever has spent time with children knows the different ways boys and girls respond to _____ situations.

A．similar 　　　　 B．same 　　　　　　 C．familiar　　　　 D．likely

14. 　　 Human beings won’t be aware of the importance of some natural resources until they ____.

A．have run out　 　　　　　　　　　　　　　 B．have brought up　

C．have broken out　 　　　　　　　　　　　　 D．have rounded up

13. 　　 -Where do you know this unique animal was found, mom?

　　 -It was on the farm_______ I visited the year before.

　　 A. that　　　　 B. when　　　　　 C. where　　　　　 D. what

12. Who do you think takes _____possession of the flat equipped with _____air conditioner?

　 　 A．the; the　　 　　　　 B．/; an　　　　 　　　　 C．/; the　　 　　　　　 D．a; an

11. 　　 -There are more than 140 species of snakes, ____ are extremely poisonous.

-Oh, really? Therefore, do be careful while traveling there!

　　 A. many of which　　 B. many of them　　　 C. few of which　　　 D. few of them