171. Im sorry to have kept you waiting so long. _.A. Thats too bad B. No, thanksC. No, not very long D. Thats all right2. There are 800 students in our school, _are girls.A. 50% of then B. 50% of whichC. 50% of whom D. 50% of the students3. He always _ sure that everything is all right with the car before he drives out.A. takes B. makes C. gets D. does4. We _ you a great success in your new experiment.A. hope B. wish C. want D. expect5. Stay _you are until I come back.A. in the place that B. asC. there D. where6. Lets go to the seaside, shall we? _.A. No, I cant B. Yes, I shallC. Yes, thank you D. No, wed better not7. She looks so sad. How I wish I_ her that!A. hadnt told B. didnt tellC. shouldnt tell D. havent told8. I dont know how you go, but one thing is certain _ you cant get there _by boat.A. other than B. more than C. less than D. rather than9. She opened her eyes and saw _ red and _ white flower.A. a, a B. a, / C. a, the D. the, the10. You need help? No, but if I do, Ill _ you to help me.A. turn to B. ask for C. look for D. depend on11. Surely his telephone number is in this book.Yes, but_, I have to look through the whole book very carefully.A. finding it B. to find itC. for finding it D. by finding it12. You must get here on time, say, at six tomorrow,_well leave without you.A. but B. and C. for D. otherwise13. Did you see him yesterday? No, but I_.A. should have B. ought toC. cannot have D. must have14. You are so tall. This little bed wont _ for you.A. do B. fit C. care D. prepare15. The well is polluted. The water isnt fit _.A. to be drunk B. for being drunkC. to drink D. drinking16. _ the villagers _ to go a long way to fetch water in those years?A. Was, used B. Had, usedC. Used, / D. Did, used17. No teacher and no student _ allowed to use these books.A. is B. are C. has D. havel8. Youll have to _ your paper carefully before you _A: look at, hand in it B. look up, turn in itC. look on, give it in D. look through, turn it in19. Another headache _ shes another difficult question to me!A. set B. made up C. asked D. put20. If you _ keep out of the trouble, you must keep your mouth shut.A. should B. willC. are going to D. are toKey:1. D 2. C 3. B 4. B 5. D 6. D 7. A 8. A 9. B 10. D 11. B 12. D 13. A 14. A 15. C 16. C 17. A 18. D 19. D 20. D解析：1Thats all right. 没关系。2whom是of的介宾。3make sure that.确保。4wish后可加双宾语。where引起地点状语从句6只有D使上下文语义通顺。7wish表“愿望”，后面为虚拟语气。8other than除了。9只用一个冠词，“红白相映的花”。10表“依靠”用depend on。11to find it, 不定式做目的状语。12otherwise不然的话。13should have (seen him) 本应该(见到他)。14wont dofor.不适合用。15be fit to drink适于饮用。16used to，可以用used提问。17这种情况要用单数的谓语动词。18look throueh查看，turn in上交。19put . to为常用搭配20bet。结构，可以表示安捧、意图等，在题中不一定非要看作将来时。