大學(xué)英語(yǔ)四級(jí)模擬試題三

時(shí)間：2024-10-25 19:18:07 學(xué)人智庫(kù) 我要投稿

相關(guān)推薦

　　Directions: There are four reading passages in this part. Each passage is followed by some questions. For each question there are four suggested answers marked A, B, C and D. You should choose the one best answer and blacken the corresponding letter on the ANSWER SHEET with a pencil.

大學(xué)英語(yǔ)四級(jí)模擬試題三

　　Passage 1

　　How do you send a message to a submerged submarine, particularly one carrying mi Water may not look like a barrier to communications, but appearances are deceiving. Water strongly absorbs all electromagnetic waves except blue green light and extremely low frequency radio waves. The very low frequency waves now used to contract submarines penetrates only a short distance into the ocean, so the craft must either surface or send up and antenna (天線) to receive messages, thereby increasing its weakness. A laser system --- accurate over long distances and capable of carrying more data than the very low frequency waves --- would talk to submarine at their normal depths.

　　In the system, a very broad beam spreading out freely in all directions would be scanned (掃描) over thousands of square miles of ocean so that it wouldn't endanger boats, birds or fish——or the submarines it is supposed to reach.

　　Since only a small fraction of the laser system will make its way through the air and ocean, receivers mounted on the submarines must be able not only to detect the laser but also to discriminate between it and sunlight. So, military scientists are now working hard on special filter that allow through only the precise wavelengths emitted by the laser. The filtered light, when transformed into electrical signal, can then be decoded. Military planners are confident that laser communication with submarines is feasible.

　　1. Which of the following does the passage mainly discuss?

　　A. Missiles carried by submerged submarines.

　　B. Messages sent by submerged submarines.

　　C. Blue-green lasers used by submerged submarines.

　　D. The way to send a message to submerged submarines.

　　2. Which of the following is TRUE according to the passage?

　　A. Water is a barrier to radio communication.

　　B. Lasers have found wide application in submarine communication.

　　C. Water absorbs all kinds of electromagnetic waves.

　　D. Very low frequency radio waves cannot be used to contact submarines.

　　3. Which of the following is NOT true of a laser system?

　　A. It is able to make its way through water.

　　B. It is able to communicate with submarines at work.

　　C. Its beam reaches a submerged submarine with the help of an antenna.

　　D. It is able to carry more data than low frequency waves.

　　4. The reference word “it” (Sentence 1, para.3) refers to .

　　A. the air

　　B. the laser beam

　　C. the ocean

　　D. the submarine

　　5. Who would be very much interested in the passage?

　　A. Missile builders

　　B. Military scientists

　　C. Fishermen

　　D. Ship builder

　　Passage 2

　　The West begun to take more notice of the East. The fifth volume of an enormous work re-assessing the Chinese contribution to science and technology is to be published next year. The first volume, which was published twenty years ago, set the tone for the whole work. In it, evidence was given to show that many inventions which, until then, western historians had claimed for Europe, were made first in China. The attempt to rewrite the intellectual history of the world was not received without protest by some reputable historians. However, the evidence that has been presented so far in the first four volumes has persuaded many historians who were skeptical at first. China's invention of paper, printing, the magnetic compass and gunpowder has never been disputed, but this new history has added advanced bridge design, mechanical clocks, paddle boats and many other inventions to the list.

　　In the four volumes published so far no attempt has been made to explain why China has not kept up with the West in science and technology in modern times. It is probable that the answer is to be found in the social and economic history of China, where a static society under a relatively benevolent regime of scholar-gentry contrasts with the potentially revolutionary and dynamic society of the West at the end of the Middle Ages. In recent years, the Chinese government has been making every effort to catch up with the West again, and there is little doubt that the gap is being reduced year by year. But will China avoid the West's mistakes?

　　6. So far, how many volumes have been published?

　　A. Five.

　　B. Four.

　　C. Three.

　　D. None.

　　7. The first volume was published .

　　A. ten years ago

　　B. last year

　　C. five years ago

　　D. twenty years ago

　　8. In Line 7, the word “skeptical" means .

　　A. doubtful

　　B. worried

　　C. sad

　　D. angry

　　9. Which of the following is not mentioned in the passage?

　　A. Gunpowder.

　　B. Needle.

　　C. Paddle boats.

　　D. Bridge design.

　　10. The best title for this passage is .

　　A. China's Inventions

　　B. Comparisons Between the East and the West

　　C. China Is Catching Up

　　D. Situations in China

　　Passage 3

　　Within fifteen years Britain and other nations should be well on with the building of huge industrial complexes for the recycling of waste. The word rubbish could lose its meaning because everything which goes into the dustbin would be made into something useful. Even the most dangerous and unpleasant wastes would provide energy if nothing else.

　　The new concept of recycling waste is taking shape at the British technological laboratory at Warren Spring, not far from the north of London. Today, the laboratory spends four times as much money in studying recycling as it did five years ago.

　　The latest project is to take a city of around half a million inhabitants and discover exactly what raw materials go into it and what go out. The aim is to find out how much of these raw materials could be provided if a plant for recycling waste were built just outside the city. This plant would recycle not only metal such as steel, lead and copper, but also paper and rubber as well. Methods have been discovered, for example, for removing the ink from newsprint so that the paper can be used again, and for obtaining valuable oils and gases from old motor car types. All these ideas are already being made use of, but what is new is the idea of combining them on such a large scale in a single plant designed to recycle most types of waste.

　　Another new project is being set up to discover the best ways of sorting and separating the rubbish. When this project is complete, the rubbish will be processed like this: first, it will pass through sharp metal spikes which will tear open the plastic bags in which rubbish is usually packed; then it will pass through a powerful fan to separate the lightest elements from the heavy solids; after that crushers and rollers will break up everything that can be broken finally, and the rubbish will pass under magnets, which will remove the bits of iron and steel; finely the rubber and plastic will then be sorted out in the final stage.

　　The first full-scale giant recycling plants are, perhaps, fifteen years away. But in some big industrial areas, where rubbish has been dumped for so long that there are no holes left to fill up with rubbish, these new automatic recycling plants may be built sooner. Indeed, with the growing cost of transporting rubbish to more distant dumps, some big cities will be forced to build their own recycling plants before long.

　　11. Projects for recycling waste in Britain .

　　A. will not be started for at least fifteen years

　　B. are being developed all over Britain

　　C. have not yet been fully tested

　　D. have been abandoned because they are too expensive

　　12. The purpose of the latest recycling project is

　　A. to prevent people from putting rubbish into holes

　　B. to find a way of destroying all kinds of waste

　　C. to extract useful raw materials from the waste

　　D. to find out how much raw materials should be provided of people want to recycle the waste

　　13. The new type of recycling plant will .

　　A. recycle only paper and rubber