10. By careful observation and precise calculation, Nicolaus Copernicus _____ that there is no one center in the universe and the sun is the center of the solar system.

　 A. believed　　 B. thought　 C. concluded　 D. imagined

9.　 ______ the aids from the outside, the positive attitude of the disaster-stricken people _____ the key role in the reconstruction of their destroyed towns and villages.

A. Except for; plays　 B. Besides; play　 C. Apart from; plays　 D. Except; play

8.　 It has been announced by our provincial government that another two medical teams will be sent to ______ the injured people in the severe earthquake.

A. join to　 B. join in　 C. take part in　 D. attend

7.　 Samples of blood from Cholera infected patients have been sent to the blood center _______.

A. to be checked　　 B. to be examined　 C. to test　 D. being tested

6.　 After several years of observation, the research group ______ the conclusion that language acquisition is faster when students ______ to the situation where it is spoken.

A. has come to; expose　　　　　　　 B. have arrived at; are exposed

C. has concluded; are exposed　　　　 D. have reached; expose

5.　 It will be many years ______the doctors and medical scientists can find _____ for cancer.

A. since; cures　 B. when; treatments　 C. before; cures　 D. until; treatments

4.　 We have to ______ everything question in detail ______ we take action.

A. conclude; before　 B. make analysis of; when　 C. expose; until　 D. analyze; before

3.　 It is clear that no use can be made ______radium _____ we don’t know clearly the characteristics of it.

A. from; if　　 B. of; unless　 C. from; unless　 D. of; if

2.　 From my point of view, the theory that ______ by the scientist is not quite scientific.

A. was risen　　 B. brought up　 C. had been raised　 D. was put forward

1.　　　 The invention of steam engine greatly sped up the industrial revolution, which _____ a lot to the take-off of the world.

A. led　　 B. contributed　 C. constructed　 D. exposed