Plastics are materials which are softened by heat and set into lasting form when shaped in a mold. Some are natural; some are semi-synthetic , the result of chemical action on natural substance; some are synthetic, built up from the constituents of oil or coal. All are based on the chemistry of carbon, with its capacity for forming chains. The molecules that compose them link together in the setting or curing process to form chains , which give plastics their flexible strength. Some plastics retain their ability to be softened and reshaped; like wax, they are thermoplastic. Others set permanently in the shapes they are given by heat and pressure; like eggs, they are thermosetting. From industrial beginnings in the nineteenth century, plastics have struggled through a hundred and twenty years of glory, failure, disrepute and suspicion on the slow road to public acceptance. Now, at last, one can positively say that plastics are appreciated and enjoyed for what they are; that they make modern life richer, more comfortable and convenient, and also more fun. Plastics are warm materials, sympathetic to the human touch, and their transformation into things that come into contact with human beings is entirely appropriate. The fact that there are plastic antiques comes as a shock to most people. How can a material that seems so essentially twentieth century, and one that is so much associated with cheap, disposable products, has a history at all? It is a young technology, and a great part of the fun of collecting plastics is that beautiful pieces of historical interest can still be found very cheaply. 21. The word sympathetic in Paragraph 2 most probably means_______. A. harmful B. agreeable C. pitiful D. sorry 22. It can be concluded from this passage that_______. A. plastics are synthetic materials B. plastics won public acceptance 120 years agoC. plastics are very harmful in modern lifeD. plastics are cheap as antiques 23. Which of the following is essential to create any type of plastics? A. Carbon. B. Eggs. C. Oil. D. Coal. 24. Plastics that harden into permanent shapes are called_______. A. chained B. thermoplastic C. synthetic D. thermosetting 25. Which of the following is the best title for the passage? A. The Importance of Plastics in the Nineteenth Century. B. Why People Are Suspicious of Plastics. C. The Development of Plastics as a Modern Material. D. How Plastics Are Manufactured. 21. B 22. D 23. A 24. D 25. C
上一篇: 英语六级考试冲刺练习阅读篇97
下一篇: 英语六级考试冲刺的练习阅读篇91
2016届高考英语考前命题动向训练:情态动词
2016届高考英语冲刺写作必考话题:8-22 unit22 environmental protection
2016届高考英语冲刺写作必考话题:3-8 unit8 adventure
2016届高考英语临考冲刺高分之路:形容词和副词
2016高考英语考纲解读及热点演练:5 连词与介词
2016届高考英语临考冲刺高分之路:主旨大意
2016届高考英语考前命题动向训练:阅读理解
2016届高考英语冲刺写作必考话题:7-20 unit20 new frontiers
2016届高考英语临考冲刺高分之路:引导名词性从句的连接词
2016高考英语考纲解读及热点演练:3 代词
2016届高考英语冲刺写作必考话题:3-9 unit9 wheels
2016届高考英语临考冲刺高分之路:中表示“本想”的6种时态
2016届高考英语冲刺写作必考话题:4-12 unit12 culture shock
2016届高考英语冲刺写作必考话题:4-10 unit10 money
2016届高考英语临考冲刺高分之路:形容词比较级和最高级表示否定意义
2016届高考英语冲刺写作必考话题:2-4 unit4 wildlife protection
2016届高考英语考前命题动向训练:作文
2016届高考英语冲刺写作必考话题:1-3 unit3 celebration
2016届高考英语考前命题动向训练:冠词介词
2016高考英语考纲解读及热点演练:2 冠词
2016届高考英语临考冲刺高分之路:虚拟语气练习题
2016届高考英语临考冲刺高分之路:虚拟语气理论详解(一)
2016届高考英语临考冲刺高分之路:延续动词与瞬间动词
2016届高考英语冲刺写作必考话题:5-13 unit13 people
2016届高考英语临考冲刺高分之路:虚拟语气理论详解(二)
2016届高考英语冲刺写作必考话题:5-14 unit14 careers
2016高考英语考纲解读及热点演练:7 时态与语态
2016届高考英语冲刺写作必考话题:2-5 unit5 rhythm
2016届高考英语冲刺写作必考话题:4-11 unit11 the media
2016届高考英语临考冲刺高分之路:一般现在时的用法