题干

突变为生物进化提供了的原始材料,下列叙述错误的是(  )

A:转基因技术实质上是DNA的重组,可定向改变生物的性状

B:体细胞杂交技术可人为引起染色体变异,它突破了自然生殖隔离的限制

C:人工诱变没有改变突变的本质,但却因突变率的提高而实现了定向变异

D:经过现代生物技术的改造和人工选择的作用,许多生物变得更符合人们的需要

上一题 下一题 0.0难度 选择题 更新时间:2011-11-29 10:56:57

答案(点此获取答案解析)

C

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阅读理解

    To develop one's taste in English, the most effective way is to read English books extensively. However, one may be at a loss to choose the suitable books, especially as a beginner. I would like to share some of my experience.

    My first English novel was Jane Austen's Pride and Prejudice, recommended (推荐) by many English teachers and professors as an ideal book for English learners. But I had great difficulty in understanding the novel, let alone enjoying it. It's not the vocabulary that troubled me, but rather the way Austen constructs sentences, and her way of thinking, which seemed too remote to me at that time. My fading enthusiasm was much recovered after reading Hemingway's novel Farewell to Arms. I particularly liked his brief and lively style. So my first suggestion is, as a beginner, you'd better choose contemporary (现代的) novels instead of classical ones.

    However, reading novels is not the only way to improve your English. English essays (散文) can at once inform you, entertain you, and improve your taste in English. The best example is Bertrand Russell's work. Its language is plain, yet you cannot help feeling the elegance and the unique sense of humor. His simple language enables his philosophy (哲理) within the reach of ordinary people. Here comes my second suggestion—essays are indispensable.

    Never follow other's opinions blindly, however famous or influential the person might be. As a saying goes, one man's meat is another man's poison. With that in mind, we are sure to find out our favorite writers through reading and develop our fine taste in English.