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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.   Glass is a remarkable substance made from the simplest raw materials. It can be colored or colorless, monochrome or polychrome, transparent, translucent, or opaque. It is lightweight impermeable to liquids, readily cleaned and reused, durable yet fragile, and often very beautiful Glass can be decorated in multiple ways and its optical properties are exceptional. In all its myriad forms – as table ware, containers, in architecture and design –glass represents a major achievement in the history of technological developments. Since the Bronze Age about 3,000 B.C., glass has been used for making various kinds of objects. It was first made from a mixture of silica, line and an alkali such as soda or potash, and these remained the basic ingredients of glass until the development of lead glass in the seventeenth century. When heated, the mixture becomes soft and malleable and can be formed by various techniques into a vast array of shapes and sizes. The homogeneous mass thus formed by melting then cools to create glass, but in contrast to most materials formed in this way (metals, for instance), glass lacks the crystalline structure normally associated with solids, and instead retains the random molecular structure of a liquid. In effect, as molten glass cools, it progressively stiffens until rigid, but does so without setting up a network of interlocking crystals customarily associated with that process. This is why glass shatters so easily when dealt a blow. Why glass deteriorates over time, especially when exposed to moisture, and why glassware must be slowly reheated and uniformly cooled after manufacture to release internal stresses induced by uneven cooling. Another unusual feature of glass is the manner in which its viscosity changes as it turns from a cold substance into a hot, ductile liquid. Unlike metals that flow or “freeze” at specific temperatures glass progressively softens as the temperature rises, going through varying stages of malleability until it flows like a thick syrup. Each stage of malleability allows the glass to be manipulated into various forms, by different techniques, and if suddenly cooled the object retains the shape achieved at that point. Glass is thus amenable to a greater number of heat-forming techniques than most other materials. Why does the author list the characteristics of glass in paragraph 1?

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What is "pop" music? It has always been difficult for me to decide (1)___________ "popular music" means music written for the people or it is simple music that the people like.The same problem of definition exists with jazz. So (2)___________ different types of music have been called jazz at one time or (3)___________ that is hard to say what it really is. Jazz has always been considered (4)___________black music but when I first took an interest in it I used to hear white bands playing music that was like Louis Armstrong's in the 1920s. I found out (5)___________ that they learn to do this by playing his records over and over again until their style was (6)___________ to his for them to imitate him. Since then white singers (7)___________ Bob Dylan have rediscovered their own folk tradition, instead of borrowing from black roots. But the main changes since 1960 have been social and technical. One is that (8)___________have more money to spend on records at an earlier age than they used to, so Tin Pan Alley, the "pop music" industry, aims at the teenage audience. Another is that electronic equipment has developed (9)___________ extent that technicians are now capable of mixing sound to produce recordings that are quite different from a live performance. But the real problem with "pop" music is that Tin Pan Alley has always worked against (10)___________ a genuine music of the people. It takes everything original and natural out of it and replaces it with cheap commercial imitation. As the American folk singer, Woody Guthrie said: "They've always preferred the second-rate song. They've never wanted to play the good one. Choose the best answer to fill in the blank.

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