题干

 请用笔画线代替导线,将背面接线示意图中连有开关的电灯和三孔插座接入家庭电路中.

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答案(点此获取答案解析)

解:灯泡接法:火线进入开关,再进入灯泡顶端的金属点,零线直接接入灯泡的螺旋套,这样在断开开关能切断火线,接触灯泡不会发生触电事故.既能控制灯泡,又能更安全.

三孔插座的接法:上孔接地线;左孔接零线;右孔接火线.如下图所示:

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阅读理解

    Science has a lot of uses. It can uncover laws of nature, cure diseases, make bombs, and help bridges to stand up. Indeed science is so good at what it does that there's always a temptation(诱惑) to drag it into problems where it may not be helpful. David Brooks, author of The Social Animal: The Hidden Sources of Love, Character, and Achievement, appears to be the latest in a long line of writers who have failed to resist the temptation.

    Brooks gained fame for several books. His latest book The Social Animal, however, is more ambitious and serious than his earlier books. It is an attempt to deal with a set of weighty topics. The book focuses on big questions: What has science revealed about human nature? What are the sources of character? And why are some people happy and successful while others aren't?

    To answer these questions, Brooks surveys a wide range of disciplines(学科).Considering this, you might expect the book to be a dry recitation of facts. But Brooks has structured his book in an unorthodox(非常规的), and perhaps unfortunate, way. Instead of introducing scientific theories, he tells a story, within which he tries to make his points, perhaps in order to keep the reader's attention. So as Harold and Erica, the hero and heroine in his story, live through childhood, we hear about the science of child development and as they begin to date we hear about the theory of sexual attraction. Brooks carries this through to the death of one of his characters.

    On the whole, Brooks's story is acceptable if uninspired. As one would expect, his writing is mostly clear and, to be fair, some chapters stand out above the rest. I enjoyed, for instance, the chapter in which Harold discovers how to think on his own. While Harold and Erica are certainly not strong or memorable characters, the more serious problems with The Social Animal lie elsewhere. These problems partly involve Brooks's attempt to translate his tale into science.