12. He made another wonderful discovery, ______of great importance to science.

A. which I think is　　　 　　　　　　　　　　　　　 B. which I think it is　　

C. which I think it　　　 　　　　　　　　　　　　　 D. I think which is

11. -Have you got ______with your composition?　

-No, I need another twenty minutes.

A. through　　　 　 B. up　　　 　　　　　　　 C. along　　 D. well

10. -When ______ and visit our factory next month?

-When ______, I’ll let you know.

A. will he come; he will come　　　　　　 　　 B. will he come; he comes

C. does he come; he will come　　　　　　 　　 D. does he come; he comes

9. Covered by the snow, ______.

A. We couldn’t find the way home　　　　　　　 B. the boy lost his way

C. the road could not be seen　 　　　　　 D. the birds couldn’t find any food

8. ______ on time, we would have to put off the trip.

A. If he doesn’t come　　　　　　　 　　　　　　　 B. If he will not come

C. If he didn’t come　　　　　　　 　　　　 D. If he wouldn’t come

7. Every means ______ prevent the water from ______.

A. are used to; polluting　　　　　 　　　　　　 B. get used to; polluting

C. is used to; polluted　　　　　　 　　　　　 D. is used to; being polluted

6. In ______, you must do your best to make the party ______.

A. a word; success　　　　　　　 　　　　 B. a word; a success　

C. one word; successes　　　　　　 　　　　 D. words ; successes

5. It is said that he is clever, ______doubt, but he is cold, too.

A. in　　　　　　 　　　 B. with　　　　 　　　　　 C. on　　　　 　　 D. no

4. The class monitor asked, “do you know who broke ______ the room last night?”

A. into　　　 　　　　 B. out　　　 　　　　　　　 C. down　　　 　　 D. up

3. ______ property should be protected in all the countries in the world， claimed the UN general secretary.

A. Knowledge　 　　 B. Intellectual　　　　 C. Thinking　　 　　 D. Thought