题干

用化学式填空(要求:化学式中的元素种类和化合价,都限于下表所列)

元素名称

化合价

+1

+6

-2

+2

①金属氧化物 ____ ;②分子中含有多个氧原子的非金属氧化物____ ;③酸____ ;④碱____ ;⑤盐 ____

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答案(点此获取答案解析)

CaO,SO3,H2SO4,Ca(OH)2,CaSO4

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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.