For almost forty years the Empire State Building in New York City was the worlds tallest

For almost forty years the Empire State Building in New York City was the world's tallest skyscraper（摩天大楼）. The building reaches a height of 1, 250 feet. It has 102 floors. The use of steel frames made its height possible. Steel walls can rise height without needing to be thick. Steel frame construction is strong. All plates are fixed firmly together by metal bolts（螺栓）called rivets （铆钉）. When set in place, rivets are usuall red- hot. One end is already rounded. A riveter uses a special hammer to shape the other end. Then the rivet cools. It holds the plates firmly. High winds can move this strong building. A wind of a hundred miles an hour has caused it to move almost one and a half inches.
　【小题1】The writer says that the Empire State Building .A．hasn’t been finishedB．is in New York CityC．is the tallest skyscraper in the world nowD．had fewer floors than the New World Trade Center　　　【小题2】In steel -frame building, the bottom walls .A．must be very thickB．must be roundedC．are usually red - hotD．do not need to be thick　　　【小题3】Rivets are described as being .A．picked up by tools when red -hotB．hit by tools when red - hotC．usually caught in a holeD．usually put in place when red - hot　【小题1】B

(答案→)　【小题1】B 解析：　【小题1】第一句话中“有四十年帝国大厦为全球最高，表明现在已不最高，但其位于纽约将不会变。　　　【小题2】第一段中“steel walls can rise high without needing to be thick”即为答案。　　　【小题3】第一段中“when set in place，rivets are usually red-hot”即为答案。

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