1.It was there, the police believe, _____ she was able to activate the recorder she kept in her bag. 　　A. until 　　B. which 　　C. that 　　D. when 　　2.It is not yet known _____ computers will one day have vision as good as human vision. 　　A. whether 　　B. if 　　C. that 　　D. how 　　3.Such attitudes amount to a belief _____ leisure can and should be put to good use. 　　A. which 　　B. if 　　C. whether 　　D. that 　　4. Many of us visited the industrial exhibition, , to our disappointment, we saw very few high-tech (高技术) products. 　　A. where 　　B. which 　　C. as 　　D. that 　　5. On the other hand concern is also growing about the possibility of a new economic order _____ resource-rich nations of the Third World would combine to set high commodity prices. 　　A. which 　　B. what 　　C. that 　　D. in that 　　6.Studies have shown _____ teenagers often suffer from depression. 　　A. that 　　B. which C .in which 　　D. in that 　　7. It is becoming increasingly clear to policy-makers schools cannot solve all the problems of the larger community. 　　A. that 　　B. what 　　C. when 　　D. who 　　9. There is no doubt _____ a large number of people have benefited from heart surgery. 　　A. what 　　B. of 　　C. if 　　D. that 　　10. Such people _____ you describe are nowadays. 　　A. as 　　B. that 　　C. who 　　D. which 　　11. Was it in that school _____ he developed his interest in physics？ 　　A. which 　　B. from which 　　C. where 　　D. that 　　12. Why do you blame him for his poor judgment on the matter _____ he really needs is encouragement？ 　　A. when that 　　B. since that 　　C. when what 　　D. now that 　　13. _____, I couldn't get a job in this company. 　　A. Try as I might 　　B. As I might try 　　C. Try though I might 　　D. I might try 　　14. It is a well-known fact ____ a person will move in a circle when he cannot use his eyes to control his direction.