21.There are over 58, 000 rocky objects in _______ space, about 900 of which could fall down onto _______ earth.
A. the; the B. 不填; the C. the; 不填 D. a; the
22. The doctor is skilled at treating heart trouble and never accepts any gift from his patients, so he has a very good_____.
A. expectation B. reputation C. contribution D. civilization
23. The fact that she was foreign made _____difficult for her to get a job in that country
A. so B. much C. that D. it
