272. The family is a cooperative enterprise for which it is difficult to _____ rules, because each family needs to work out its own ways to deal with its own problems.

　A. set up B. put down C. keep up D. lay down

271. Although hehasn't any formal qualifications, Betas _____ to do well for himself.

　A. managed B. succeeded C. arranged D. convinced

270. John always tries to _____ people who are useful to him professionally.

　A. develop B. provoke C. correspond D. cultivate

269. What a terrible experience! _____ , you are safe, that's the main thing.

　A. Somehow B. Anyhow C. Somewhat D. Anywhere

268. He has recently _____ chess to provide himself with some relaxation.

　A. taken on B. taken up C. held on D. held up

267. It has been decided that this company has the _____ right to print Mr. Smith's novels.

　A.eventual B.versatile C.extensive D.exclusive

266. Jim's close _____ to his brother made people mistake them for one another.

　A. confusion B. similarity C. resemblance D. imitation

265. I think we should let Maria go camping with her boyfriend. _____, she's a big girl now.

　A.Above all B. After all C. First of all D. For all

264. During World War II Malta managed to _____ most of Italian and German bombers by throwing up an effective anti-aircraft screen.

　A. put out B. shut out C. come across D. get across

263. The room was so quiet that she could hear the _____ of her heart.

　A. hitting B. beating C. tapping D. knocking