听力原文:The vast oceans of the world are dark, deep and mysterious places where eyesight - 试题答案网问答

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：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3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4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：As China's vast interior gets richer, Grenda Lee, Coco-Cola's Shanghai-based dire

ctor of external affairs, finds herself dreaming about tapping the country' s rural market. Chinese peasants account for roughly 70 percent of China's 1.3 billion people, but on average each drinks only three Coke products a year. That compares with some 60 drinks consumed annually in Shanghai and Beijing, 150 in Hong Kong and 420 in the United States. With so many customers at stake, potential profits take on epic scale.

The annual consumption of Coco-Cola per capita in the regional markets mentioned in the passage ranks in the following order.

A．Rural China, Beijing, the United States, Hong Kong.

B．Beijing, the United States, Rural China, Hong Kong.

C．The United States, Hong Kong, Shanghai, Rural China

D．Shanghai, Rural China, the United States, Hong Kong.

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第8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9题

听力原文： We experience different forms of the Sun's energy every day. We can see its ligh

t and feel its warmth. The Sun is the major source of evaporation of water from the oceans and lakes. Sunlight also provides the energy used by green plants to make their own food. These green plants then provide food for all organisms on the Earth.

Much of the energy that comes from the Sun never reaches the Earth's surface. It is either reflected or absorbed by the gases in the upper atmosphere. Of the energy that reaches the lower atmosphere, 30% is reflected by clouds or the Earth's surface. The remaining 70% warms the surface of the planet, causes water to evaporate, and provides energy for the water cycle and weather. Only a tiny part, approximately 0.023%, is actually used by green plants to produce food.

Many gases found in the atmosphere actually reflect heat energy escaping from the Earth's surface back to the Earth. These gases act like the glass of a greenhouse in that they allow energy from the Sun to enter but prevent energy from leaving. They are therefore called greenhouse gases.

When sunlight strikes an object, some of the energy is absorbed and some is reflected. The amount reflected depends on the surface. For example, you've probably noticed how bright snow is when sunlight falls on it. Snow reflects most of the energy from the Sun, so it contributes to the low temperatures of winter. Dark-colored surfaces, such as dark soil or forest, absorb more energy and help warm the surrounding air.

What is the major source of evaporation of water from the oceans and lakes？

A．The moon.

B．The sun.

C．The star.

D．The earth.

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第10题

听力原文： Scientists believed that when the oceans were young, they contained only a trait

of salt, and that the level of salinity have been growing gradually. Over the years the rain had worn away the rocky mantle of the continents. Minerals released by this erosion had been carried to the sea by the flow of river water. This water added several million tons of salt to the ocean annually. There are other sources of oceanic salinity too. One source is under water volcanic action. This eruption occurs along the mid-ocean range and release great amount of salt each year. However these sources of salt don't increase the actual mineral composition of water by much, because of the enormous chemical requirements of marine life. Oyster, clam, snails and other louse use salt to build shells and skeletons. Coral reefs also contains large amount of salts. Also some salt leave the ocean through the process of evaporation. As salt escape into the atmosphere, they go into the creation of rain drops. This is why the coast received more rain than land area. You see, more salt existence in the atmosphere near the ocean, thereby attracting increased moisture and producing rain.

What is the topic of this talk？

A．The salinity of the ocean.

B．Pollutants found at sea.

C．The composition of coral reefs.

D．The weather patterns of coastal areas.

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