听力原文:The vast oceans of the world are dark, deep and mysterious places where eyesight

第1题

听力原文： The vast oceans of the world are dark, deep and mysterious places where eyesi

ght counts for little as soon as you venture very far beneath the surface. For humans, who live in a world dominated by visual stimuli, to exist in such conditions would be impossible. But for whales and dolphins that live in the ocean or, in the case of a few species, muddy rivers, the darkness is unimportant. What is important to them is sound. Sound is an efficient way to transmit and sense information, especially as it travels five times faster through water than through air. If humans shout to someone, it is unlikely that they will be heard a kilometre away. But if a whale shouts in an ocean channel, another whale may hear it tens, if not hundreds, of kilometres away. Whales and dolphins use sound in two ways: for communication and for echolocation. Dolphins and toothed whales communicate through a wide variety of high-frequency sounds. But as well as using sounds to communicate, toothed whales and dolphins also rely on echolocation to learn about their immediate environment, including prey that might be waiting nearby. They produce intense short broad-band pulses of sound in the ultrasonic range. These clicks are brief, typically less than one millisecond long — but they are repeated many times each second. Questions 16 to 18 are based on the passage you have just heard. 16. For whales and dolphins, which sense is most important？ 17. How much faster does the sound travel in the water than in the air？ 18. How do the dolphins and toothed whales communicate？17．

A．Six times.

B．Five times.

C．Three times.

D．Two times.

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第2题

听力原文：Why do people want to save the Whales？ There are two important reasons. One reaso

听力原文： Why do people want to save the Whales？ There are two important reasons. One reason is that whales help to keep a balance between plants and animals. People have disturbed this balance. People get rid of their wastes by throwing them into the oceans and seas. People's sewage and garbage increase the salt in ocean and sea water. The increased salt helps some plants and some very small animals to grow. These plants and animals can be harmful to fish. Whales eat enormous amount of plants and animals that grow in very salty water. Therefore, whales are very important because they keep the ocean environment clean enough for fish. In addition, because fish provide necessary food for many people, people need whales, and many people want to save them.

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A．Because whales keep a balance between plants and animals on land.

B．Because whales eat a lot of fish.

C．Because whales eat large amounts of garbage.

D．Because whales keep oceans clean for fish, and people need fish.

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第3题

听力原文：The water level of oceans rises and falls alternatively twice a day. This movemen

听力原文： The water level of oceans rises and falls alternatively twice a day. This movement of water is called the tide. Tides are caused by the pull of the sun and the moon on the earth's surface; since the moon is much closer, it affects the tides more than the sun. When the moon is directly overhead, it actually pulls on the water that is below it. This causes the water level to rise because the water is pulled away from the earth. As the moon disappears over the horizon, the pull lessens and the water level settles back towards the ocean bottom.

When the water reaches its highest level, we have high tide. And when the water reaches its lowest level, we have low tide. From its lowest point, the water rises gradually for about six hours until it reaches high tide. Then it begins to fall continuously for about six hours until it reaches low tide. Then the cycle begins again.

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A．Every other day.

B．Twice a week.

C．Twice a day.

D．Only during the summer.

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第4题

听力原文：World Environment Day was established by the United Nations General Assembly in 1

听力原文： World Environment Day was established by the United Nations General Assembly in 1972 to mark the opening of the Stockholm Conference on the Human Environment. World Environment Day can be celebrated in many ways, including street rallies, bicycles parades, green concerts, essay and poster competitions in schools, tree planting, recycling efforts, clean-up campaigns and much more.

Heads of State, Prime Ministers and Ministers of Environment deliver statements and commit themselves to care for the Earth. World Environment Day, commemorated each year on 5 June is one of the principal vehicles through which the United Nations stimulates worldwide awareness of the environment and enhances political attention and action. The World Environment Day theme selected for 2004 is Wanted! Seas and Oceans—Dead or Alive？ The theme asks that we make a choice as to how we want to treat the Earth's seas and oceans. It also calls on each and every one of us to act. Do we want to keep seas and oceans healthy and alive or polluted and dead？

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A．In 1992.

B．In 2000.

C．In 2004.

D．In 1972.

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第5题

听力原文：Scientists are gearing up for one of the most ambitious international research pr

听力原文： Scientists are gearing up for one of the most ambitious international research programs ever attempted: a decade-long exploration of the world's oceans to unlock some of the most closely held secrets of the creatures of the deep. Using sophisticated technology that was not available even five years ago, the scientists will rely primarily on the animals they want to study to collect the data needed to complete the "Census of Marine Life". Creatures ranging from blue whales to turtles will be fitted with satellite tracking devices that will record their every movement. The project, involving scores of institutions around the globe, is expected to cost upwards of $1 billion, and it will take at least 10 years. The scientists hope the research will tell us much more about a region of the earth we understand so poorly. That area, incidentally, covers 70 percent of the globe.

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A．10 years.

B．20 years.

C．30 years.

D．50 years.

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第6题

听力原文：A good way to see the USA is by car. Americans love their automobiles and in the

听力原文： A good way to see the USA is by car. Americans love their automobiles and in the past fifty years they have developed a vast network of roads and freeways to help them reach their destinations. As few visitors have their own cars, renting one is the next best thing. You will need a valid driver's license and either international credit cards, or a deposit.

You should start out with a working knowledge of the road. Regulations vary from state to state and this can be very confusing to a newcomer. For example, in some states it is legal to turn right at a red light if there is no approaching traffic, while in other states you will be fined for this action. Throughout the country it is forbidden to pass a school bus when it has stopped to let off children.

The size of the country may startle you at first and you may be surprised at the spectacular physical beauty. When the first pioneers began to expand West into the wildness, the natural resources of the land seemed inexhaustible. Nearly 1,000 million acres of land was covered by virgin forests. Much of this was burnt off for farmland and it soon became apparent that the government would have to take action or the natural beauty of the land would be lost for ever.

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A．A driver's license.

B．A passport.

C．An international credit card.

D．A deposit.

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第7题

听力原文：A: How is Canada's climate？ Is it intolerably cold in winter？B: People tend to th

听力原文：A: How is Canada's climate？ Is it intolerably cold in winter？

B: People tend to think that as Canada is a northern country, its winters must be harsh and long. But contrary to the popular belief, on the whole, Canada is a very sunny land with a distinctive change of seasons. Of course, since Canada is such a vast country, its climate varies greatly from region to region.

A: Really？ That sounds amazing to me.

B: Yes, when talking about Canada's climate, people usually divide it into six climatic regions.

A: In general, how are the four seasons divided？

B: Generally speaking, spring begins in mid March and ends in mid May. It is regarded as a transitional time in Canada. Summer lasts for about four months. Autumn is the shortest season, less than about three months. Winter is the longest season in most of Canada.

A: Is summer in Canada very hot？

B: No. The summer in Canada is warm and sunny. For most people, it is the best season for fun and relaxation.

A: How about autumn？

B: Autumn is very beautiful, though it is brief.

A: Is winter in Canada terribly cold？

B: Well, the winter in Canada is indeed very long, but it is not gloomy because there is much sunshine. So many people enjoy skiing and skating in winter.

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A．Harsh and long.

B．Gloomy.

C．Long but sunny.

D．Terrible.

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第8题

听力原文：M: How did you like yesterday's astronomy class？W: It was interesting. But the po

听力原文：M: How did you like yesterday's astronomy class？

W: It was interesting. But the point she was trying to make seemed a little far-fetched.

M: Oh, that new theory that ocean water came from comets？

W: Yeah. Do you remember what it was based on'？

M: Some recent satellite photos, I think. Apparently, Space satellites recently detected thousands of small comets colliding with earth's outer atmosphere, almost 40,000 per day.

W: OK, they're collided with atmosphere. So that's what created the water？

M: It's not the collision that created water. Comets contain water. They're made up mostly of cosmic dust and water. When they collide with the atmosphere, they break up. And the water they contain rains down to earth. Ocean water came from that rain.

W: Oh well, this morning I asked my geology professor about that. He said that most geologists don't accept it.

M: Why not？

W: Special research indicates that most of the water molecules from the comet would have burned up as they fell through the atmosphere. Enough rain couldn't have reached the earth to fill up the ocean.

M: Well, did the geologists have an alternative theory to explain where ocean water came from？

W: Yeah, he said the more traditional view is that the ocean water came from volcanoes.

M: From volcanoes？

W: Right. They say volcanic fumes are mostly steam. And they claimed that it was the volcanic steam that created the oceans, not rain from comets.

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A．The effect of the atmosphere on rainfall.

B．How conditions on earth support life.

C．How water originated on earth.

D．A new estimate of the age of earth.

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第9题

听力原文：In a scientific context, the word "chaos" bas a slightly different meaning than i

听力原文： In a scientific context, the word "chaos" bas a slightly different meaning than it docs in its general usage as a state of confusion, lacking any order. Chaos, with reference to chaos theory, refers to an apparent lack of order in a system that nevertheless obeys particular laws or rules. The two main components of chaos theory are the ideas that systems—no matter how complex they may be—rely upon an underlying order, and that very simple or small systems and events can cause very complex behaviors or events.

The Earth's atmosphere is a chaotic system with regularly occurring weather phenomena like wind, cloud, rain, snow, fog and dust storms and less common events(natural disasters) like tornadoes, hurricanes and ice storms, so small changes to one part can have large effects elsewhere. This makes it very difficult to accurately predict weather changes more than a few days in advance, though weather forecasters are continually working to extend this limit through the scientific study of weather, Meteorology.

Chaos theory says that the slightest variation in the motion of the air will grow with time. This idea is sometimes called the butterfly effect, from the idea that the motions caused by the flapping wings of a butterfly eventually could produce marked changes in the state of the atmosphere. Because of this sensitivity to small changes it will never be possible to forecast perfectly, although there still is potential for vast improvement.

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A．A state of confusion, lacking any order.

B．Chaos theory.

C．An apparent lack of order in a system.

D．Obeys particular laws or rules.

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第10题

听力原文： There is probably no place anywhere in 'the civilized world today that is not vi

sited by tourists. The travel business offers a vast network of services for the comfort and convenience of travelers. "Package tours" that include almost everything from transportation to hotels, meals and sightseeing trips are offered by airlines, railroads and bus fines. Some steamship companies specialize in travel to different parts of the world. There are also private agencies that organize tours for young people at the age of fourteen and over.

A visitor to a strange land today need never be at a loss for information about the place he is visiting. There are iunumerable travel books and guide books for practically every spot on the globe. The books advise what to see, eat, wear, and buy, and describe restaurants, hotel, and special shopping places. Governments, states and cities publish books or maps listing important sights for visitors.

People may make their own arrangements for a trip, or they may prefer to use the services of a travel agency. A travel agency will order transportation tickets, reserve hotel rooms, and arrange for anything. Travel agencies, some run by governments, are to be found in every country.

What is the best title for this passage？

A．Travel books.

B．Travel agencies.

C．Package tours.

D．Travel.

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听力原文：The vast oceans of the world are dark, deep and mysterious places where eyesight