试题库在线考试题库-历年真题模拟试题及答案-考博英语在线试题测试中心-希赛网

湘潭大学

The solar system is made up of the objects that move around our sun in a regular path. Things were not always this way. The sun and the objects that encircle it started out in a very different form.It is believed that our solar system began as a large cloud of gas and dust. The cloud had a round shape and spun slowly. The spinning caused the gas and dust to flatten into a large disc. The mass of gas and dust at the center became the sun. The gas and dust were pulled together by gravity so that nuclear reactions started. The rest of the dust and gas outside of this moved so slowly that it started to cling together in places. Eventually, enough material stuck together to form planets.There are many different objects in our solar system. Of course, there are planets. Each one is unique. Some planets are made of rock or metal elements. Mercury, Venus, Earth, and Mars are like this. Other planets are more like gas and ice. Jupiter, Saturn, and the others are like this. The planets have moons — sometimes more than one.Our solar system has a major asteroid belt. An asteroid is basically a rock. The largest is about 10km across. Huge numbers of these rocks circle the sun between Mars and Jupiter. Sometimes the asteroids crash into each other and move towards Earth. When they pass near our planet, they heat up and burn. We see them as shooting stars.Lastly, there are comets which are made of ice and gas. They also go around the sun but not with a normal path. When they are near the sun, they start to melt and form a tail. Far from the sun, where space is cold, the comets remain frozen solid.1. All of the following are mentioned in paragraph 2 EXCEPT（）.2. The word this in paragraph 3 refers to（）.3. According to paragraph 4, what happens when an asteroid burns near our planet?

The long, wet summer here in the northeastern U.S. notwithstanding, there’s a world shortage of pure, fresh water. As demand for water hits the limits of finite supply, potential conflicts are brewing between nations that share transboundary freshwater reserves.Many people ask why we cannot simply take it from the sea, using our sophisticated technology of desalinization. But a good water supply must be hygienically safe and pleasant tasting and water containing salt would corrode machinery used in manufacturing in addition to producing chemical impurities. Since more than 95% of our water sits in the salty seas, man is left to face the reality that most water on the surface of the earth is not available for us.One very feasible way of sustaining our supply of freshwater is to protect the ecology of our mountains. Mountains and water go together, a fact to which Secretary General Kofi Annan has drawn attention more than once. From 30% to 60% of downstream fresh water in humid areas and up to 95% in arid and semi-arid environments are supplied by mountains. Without interference nature has its own way of purifying water—even though chlorination and filtration are still necessary as a precaution. In a mountainous area, aeration, due to turbulent flow and waterfalls, causes an exchange of gases between the atmosphere and the water. Agriculture, industry, hydroelectric generators and homes that need water to drink and for domestic use depend on these resources and, thus, we must protect mountainous areas as a means of survival.1. The author of this text states that（）.2. The author believes that industry avoids salt water because（）.3. The best title for this text is（）.

Travel operator Sandersley is different from most of its rivals. UK package holiday companies are operating in a very competitive market. In an effort to attract trade, they are forced to spend enormous sums on marketing. Although big travel companies try hard to create attractive brands, if you ask the customers delayed at airports, many aren’t even sure which company they’ve booked with. Asking customers of Sandersley, however, they would say this is probably their third or fourth holiday with the company.A Sandersley holiday doesn’t come cheap; but for their customers this isn’t an issue. A high proportion of its customers are families, because the adults are free to enjoy the activities on offer, while small children are in the care of people employed by Sandersley just for this purpose. These nannies get free flights and meals on top of their pay.Interestingly, most of the company’s senior managers began at the bottom: for example, Carol Fletcher, the Marketing Manager, came as a ski guide in 1985, went away to set up her own catering business, sold it for a considerable sum, and returned to Sandersley in the late 1990s.The company’s performance over the years means that it gets a steady stream of offers from large tour operators wanting to buy the company. Jerry Baker, who started the firm, came very close to selling it for £30 million a few years ago. But at the last minute, Garmond, the potential buyer, was itself taken over by an American travel company which didn’t see a place for Sandersley in the group.Despite greatly increasing its turnover in the past four years, the company has a careful attitude to expansion. Its decision not to sell skiing holidays in North America proved the right one when many of its rivals failed to persuade British travelers to take the ten-hour flight. Learning from experiences like these, Sandersley’s two recent departures from its main activity are the acquisitions of restaurant chains in Spain and in Turkey.1. Sandersley differs from most other UK travel operators in（）.2. The company attracts families because（）.3. In what way is Carol Fletcher typical of the company’s senior staff?4. Sandersley was not sold because（）.5. What is Sandersley’s strategy for expansion?

The new miracle of the medical world is the stem cell, a marvel of human nature in that it can become any of nearly 220 cell types that constitute the human body. It is often called a blank cell that can be programmed to become other cells. Researchers predict that, by using stem cells, they can create organs that can be transplanted into people who desperately need them to save their lives. The most common source of stem cells is the human embryo, the initial stage of human life after a female egg is impregnated by a male sperm. In this very fact lies an ethical conundrum that has rocked both the medical and political landscape of the United States and other countries. Coupled with this is new research in cloning, which has seen some success in developing animal species without the use of normal birthing procedures. All of these areas of research are making quite a few people nervous about both the sources of stem cells and where the research is taking mankind.Most stem cell-containing embryos come from four different sources: fertility clinics, which often store more human embryos than are needed; fetuses from unwanted pregnancies that are aborted; therapeutic cloning, which is when a human egg is stimulated into an embryo-like state; and custom-fertilization, in which a human egg is deliberately fertilized with sperm to create an embryo in order to harvest its stem cells. Morally, many people are outraged by these sources, claiming that human life is not something that should be tampered with and created just for scientific and medical purposes. At the core of this debate is the issue of what really constitutes a human being, with one side claiming a human does not exist until born rom its mother while the other side claims that once egg and sperm meet, life has begun.The United States government has taken an active role in the debate and is consciously looking at the voting booth while making decisions regarding stem cell research. The government gave the go-ahead for federal spending on stem cell research but limited activity to specimens that already existed, meaning no new embryos could be created solely for stem cell research. Similar laws regarding cloning research have been proposed, including therapeutic cloning. Many universities and research centers worry that these laws may cause their best and brightest scientists to seek appointments overseas, where stem cell research is not so controversial.Scientists now seek non-embryonic sources of stem cells to avoid the controversy in the future and to allow them to carry out their work without interference. Unfortunately, so far the search has not unearthed any sources that are as perfect as human embryo stem cells. The main reason they are not perfect is that, while embryo stem cells can become any other cell, other stem cells from different sources can only become limited types of cells. Research suggests that inside each person there is a limited supply of stem cells in the blood that are used to repair red blood cells when they are damaged. Some scientists believe they may be able to harvest these cells, but results so far have had limited success in extracting and using them to produce other cells. Even the limited successes they have had are being questioned by other experts as unproven. Two other sources, baby teeth and adult bone marrow, show some possibilities, but again the research is being questioned, and, as of yet, no positive new source of stem cells has been found to replace human embryos.In view of the ethical debate that surrounds stem cell research, especially its sources of stem cells, it is likely that it will be some time before the whole issue is laid to rest. Meanwhile, countless people suffer from illnesses that could be cured or their pain alleviated by the work that comes from stem cell research. Some people believe that the debate about when human life actually begins needs to take a backseat to the issue of when human life will end, especially when it is possible to save someone from an early death. In the end, the research will likely get done in a place that puts existing human life above that in the embryonic state. It is also highly unlikely that that place will be the United States.1. According to paragraph 1, a stem cell is unlike other cells because（）.2. According to paragraph 2, the main debate concerning stem cell sources revolves around（）.3. According to paragraph 3, American universities and research institutes are worried about（）.4. Which of the sentences below best expresses the essential information in paragraph 3. Incorrect answer choices change the meaning in important ways or leave out essential information.5. It can be inferred from paragraph 5 that in many countries stem cell research（）.

Sociologists use the term “power” to refer to the（1）of people or groups to control or influence the actions of others,（2）those others wish to cooperate or not. Sociologists study power to determine not only who exercises it and who（3）from its use, but also why it is exercised.Of the three main types of（4）—wealth, power, and prestige—power is the hardest to measure. Most studies of power are（5）more than an average of guesses about where power is found. Many forms of power are so well（6）that only the power holders know their source. Because it is so hard to measure and（7）it is so tied to questions of ideology, the subject of power—who holds it and how it is used—is a source of much debate（8）sociology. Some sociologists maintain that power in America is concentrated in（9）of a few people who have a common background and who tend to act together. Wright Mills suggested that America is run by a “power elite” and set（10）total number at no more than 300 people. Other sociologists believe that power in America is（11）among many groups and people. However, Sociologists（12）agree that real power may not always lie where we think it does. The mayors of some cities,（13）, are sometimes mere figureheads who simply look impressive. The actual decisions are made by a handful of business leaders who stay（14）the scenes. And some decisions are made at the lowest level,（15）the work is really carried. Such is the case with a policeman on the beat or a teacher in the classroom. Clearly, power（16）exist without wealth: Not all the rich are powerful, and not all the powerful are rich. But the two（17）are closely related. Wealth can sometimes buy power in international politics, for instance, candidates（18）office are often wealthy. The Kennedy brothers, the three Rockefeller governors are examples of men of（19）who have become powerful in politics. Moreover, power is often used to acquire wealth. How many lawmakers or labor union heads retired in（20）?

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