题目内容
Part A
Directions: Read the following texts and answer the questions which accompany them by choosing A, B, C or D. Mark your answers on ANSWER SHEET 1.
The Stone age, the Iron age. Entire epochs have been named for materials. So what to name the decades ahead？ The choice will be tough. Welcome to the age of superstuff. Material science—once the least sexy technology—is bursting with new, practical discoveries led by superconducting ceramics that may revolutionize electronics. But superconductors are just part of the picture; from houses and cars to cook pots and artificial teeth, the world will sometime be made of different stuff. Exotic plastics, glass and ceramics will shape the future just as surely as have genetic engineering and computer science.
The key to the new materials is researchers' increasing ability to manipulate substances at the molecular level. Ceramics, for instance, have long been limited by their brittleness. But by minimizing the microscopic imperfections that cause it, scientists are making far stronger ceramics that still retain such qualities as hardness and heat resistance. Ford Motor Co. now uses ceramic tools to cut steel. A firm called Kyocera has created a line of ceramic scissors and knives that stay sharp for years and never rust or corrode.
A similar transformation has overtaken plastics. High-strength polymers now form. bridges, iceskating rinks and helicopter rotors. And one new plastic that generates electricity when vibrated or pushed is used in electric guitars, touch sensors for robot hands and karate jackets that automatically record each punch and chop. Even plastic litter, which once threatened to permanently blot the landscape, has proved amenable to molecular tinkering. Several manufacturers now make biodegradable forms; some plastic six-pack rings for example, gradually decompose when exposed to sunlight. Researchers are developing ways to make plastics as recyclable as metal or glass. What's more, composites—plastic reinforced with fibres of graphite or other compounds—made the round-the-world flight of the voyager possible and have even been proved in combat:a helmet saved an infantryman's life by deflecting two bullets in the Grenada invasion.
Some advanced materials are old standard with a new twist. The newest fiberoptic cables that carry telephone calls cross-country are made of glass so transparent that a piece of 100 miles thick is clearer than a standard window pane.
But new materials have no impact until they are made into products. And that transition could prove difficult, for switching requires lengthy research and investment. It can be said a firmer handle on how to move to commercialization will determine the success or failure of a country in the coming future.
How many new materials are mentioned in this passage？
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听力原文：W: We hope you enjoy your stay here at the hotel. Here is your room key and by the way checkout time is at noon.
M: Oh. thanks for reminding me. It's a lovely hotel and I'm not at all in a hurry to leave, but I wouldn't want to be charged for. a second night.
Q: What will the man probably do？
(17)
What/Who should students contact if they want to get a summer job？
听力原文： Why are college students so prone to sleep deprivation？ The problem often begins during the teen years. Most high school kids admit that they are often sleepy and 15 percent admit that they fall asleep in class.
Lack of sleep causes many problems, not the least of which is the difficulty it adds to learning. It's also detrimental to the immune system and motor skills. Students (and everyone else) need at least eight hours of sleep to maintain optimum health and learning capabilities. Yet, with the pressure of school, family and social life, few students are sleeping near the required amount.
College life only escalates the problem. Added to the above activities are more hours needed for studies. Some students also hold down a part time job to help defray college expenses. Some students are married and trying to support a family. Because of all these pressures there is also an increase in stress. Stress can lead to insomnia and even more lost sleep.
With the approach of finals, the problem can only grow worse. Students force themselves to stay awake to study. It's called cramming for exams, and it can eat away at sleep hours already far too meager. Too many nights of forced wakefulness can eventually lead to a ease of full-blown insomnia and other sleep abnormalities.
(36)
听力原文：M: Did you hear about the air crash that occurred in South America recently？ It was quite a tragic accident!
W: No, I didn't see anything in the news about it. What happened？
M: A foreign airliner was attempting to land at night in a mountainous area in Argentina and flew into a hill!
W: That sounds really terrible! Did anyone survive？
M: No, everyone aboard, including the crew, was killed instantly.
W: What were the circumstances？ Were they bad weather, a fire, or engine failure？
M: Apparently, there were some low clouds in the area, but mostly it was just miscommunication between the pilots and the air traffic controllers.
W: Weren't they both speaking in English, the official international aviation language？
M: Yes they were, but the transition from poor quality radios was slightly distorted and the accents of the Spanish speaking controllers was so strong that the pilots misunderstood a vital instruction.
W: How could a misunderstanding like that cause such a serious accident？
M: The pilots were told to descend to 22, 000 feet. The instruction actually meant22, 000 feet, but they thought they heard descend 2, 000 feet. That's a huge difference, and it should have been confirmed, but it was not. Unfortunately, the terrain of the mountains in Norweija ascend to 2, 000 feet.
W: So the pilots did descend to the wrong altitude then, because they were following the air controller's instructions.
M: Sadly enough, yes they did. It was a really bad mistake. Many people died as a result of the simply misunderstanding.
W: Wow, that's a powerful lesson on how important it can be to accurately communicate with each other.
What was the cause of the tragedy？
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