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英語六級考試試題精選練習

　　學習中要蕩起“樂學”和“巧思”的雙槳，倡導“書山有路巧為徑，學海無涯樂作舟”的學習態(tài)度和方法，這樣才能學得生動活潑、融會貫通。以下是小編為大家搜索整理的英語六級考試試題精選練習，希望對正在關注的您有所幫助!更多精彩內(nèi)容請及時關注我們應屆畢業(yè)生考試網(wǎng)!

英語六級考試試題精選練習

　　part 1

　　The difference between a liquid and a gas is obvious under the conditions of temperature and pressure commonly found at the surface of the Earth. A liquid can be kept in an open container and fill it to the level of a free surface. A gas forms no free surface but tends to diffuse throughout the__1__available; it must therefore be kept in a closed container or held by a gravitational field, as in the__2__of a planet's atmosphere. The distinction was a __3__feature of early theories describing the phases of matter. In the nineteenth century, for example, one theory maintained that a liquid could be "dissolved" in a vapor without losing its identity, and another theory__4 __that the two phases are made up of different kinds of molecules. The theories now prevailing take a quite different approach by emphasizing what liquids and gases have in __5 __They are both forms of matter that have no __6 __structure, and they both flow readily.

　　The fundamental similarity of liquids and gases becomes clearly apparent when the temperature and pressure are __7__somewhat. Suppose a closed container __8__filled with a liquid is heated. The liquid expands, or in other words becomes less dense; some of it evaporates. In contrast, the vapor above the liquid surface becomes denser as the evaporated molecules are __9__to it. The combination of temperature and pressure at cet6w.com become __10__is called the critical point.

　　A. added B. case C. prominent D. held

　　E. equal F. partially G. example H. previous

　　I. space J, lifted K. permanent L. particularly

　　M. extended N. raised 0. common

　　參考答案

　　I. I 2. B 3. C 4. D 5. O 6. K 7. N 8. F 9. A 10. E

　　part 2

　　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(半合成的) , 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 (monomers) link together in the setting or curing(硫化) process to form chains (polymers) , 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.

　　1. The word "sympathetic" in Paragraph 2 most probably means_______.

　　A. harmful B. agreeable

　　C. pitiful D. sorry

　　2. It can be concluded from this passage that_______.

　　A. plastics are synthetic materials

　　B. plastics won public acceptance 120 years ago

　　C. plastics are very harmful in modern life

　　D. plastics are cheap as antiques

　　3. Which of the following is essential to create any type of plastics?

　　A. Carbon. B. Eggs.

　　C. Oil. D. Coal.

　　4. Plastics that harden into permanent shapes are called_______.