Air is all around us. It is around us when we walk and play. From the moment we are born, - 试题答案网问答

第1题

Without the atmosphere, there would be no weather, no wind, rain, snow, or clouds. Air is

all around us; we live at the bottom of a great ocean of air. It is invisible, but we can feel it when it moves. There are miles of all above us, pressing down with great weight on the earth and everything on it. Because air presses down on us from all directions at the same time, and because we are able to bear (忍受) this weight, we do not seem to feel it. But scientists have proved that air has this weight, and that anything that has weight creates (产生) a force called pressure. As changes in air pressure take place, they make air move.

Air is a gas that expands (膨胀) when heated, gets lighter, and moves upward. When air is

cooled, it gets heavier, sinks close to the earth's surface, and flows like water in a great river. As warm air rises, cold air rashes to take its place. Thus winds originate (起源). Tile winds that blow high above us are caused by the warmer air running away from colder air. The wind we feel near the earth's surface is the heavy colder air trying hard to catch the warmer air. Changes in temperature cause the air to move. And of course there are many changes, so air movements are taking place practically all the time.

The first paragraph mainly tells us______.

A．why we don't feel air

B．why atmosphere is important to us

C．why there is air surrounding us

D．why there is air pressure

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第2题

听力原文：In a way, all of us are on a spaceship, the planet Earth. We move around the sun

听力原文： In a way, all of us are on a spaceship, the planet Earth. We move around the sun at 18 miles per second and never stop. On our spaceship we have six billion people and a limited supply of air, water, and land. These supplies have to be used carefully because we can't buy new air, water, or land from anywhere else.

The environment on our planet is a closed system: nothing new is ever added. Nature recycles its resources. Water, for example, evaporates and rises as visible drops to form. clouds. Then the water returns to earth as rain or snow. The rain that falls today is actually the same water that fell on the land 70 million years ago.

Today, the Earth is in trouble. Factories pour dirty water into rivers. Many fishes die and the water become unhealthy for people to drink, Cars and factories put poisonous gas into the air and cause plants, animals and people to get sick. People throw bottles and paper out of their car windows, and the roadside becomes covered with all sorts of wastes. Over the years, people have changed the environment, and at the same time we cause pollution.

To continue to survive, we must learn how to use the Earth's resources wisely. We have to change our habits and stop dumping such enormous amounts of industrial waste into the water and air. We must cooperate with nature and learn better ways to use, not abuse, our environment.

(37)

A．Because both have a limited supply of air, water, and other resources.

B．Because the Earth moves around the sun as fast as a spaceship.

C．Because we can travel to outer space.

D．Because the Earth never stops moving.

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第3题

听力原文：Ladies and gentlemen, attention, please. Our bus will arrive at Lake District in

a few minutes. You can feel the comfortable cool air coming from the lake. This is a favorite place for tourists in summer, especially on a hot summer afternoon like today. This area is one of the British national parks. People began to build houses around the lake a hundred years ago, so in this park you can have a special view of houses of all shapes and styles and colors. In late autumn and winter, this park is the best place for an outing. People like to have a good walk around it. Now our bus is driving around the lake. You can sit back and enjoy the beauty of everything here. The bus will take us to a good spot, where you can take the most wonderful photos you have ever taken.

Here we are! Where we get off is where we get on. Return to the bus in Fifty minutes. Thank you!

Who do you think is speaking？

A．A bus driver.

B．A tourist guide.

C．A visitor.

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第4题

听力原文： Spaceships travel around the earth, go to the moon, and return home safely. T

he astronauts carry important supplies with them on the spaceship — food, water and air. Sometimes there are problems on the spaceship, and the astronauts have to understand how the spaceship works in order to repair the problems. In a way, all of us are really on a spaceship, the planet Earth. We move around the Sun at 18 miles per second and never stop. On our spaceship we have four billion people and a limited supply of air, water and land. These supplies, just like the limited supplies on the astronauts spaceship, have to be used carefully because we cant buy new air, water or land from anywhere else. Everyone needs air, water and land to live — this is our environment. The environment on our planet is a closed system; nothing new is ever added. Nature recycles its resources. Water, for example, evaporates and rises to form. clouds. This same water returns to the earth as rain or snow. The rain that falls today is actually the same water that fell on the dinosaurs 70 million years ago. Over the years, people have changed the environment. We have poured back into the land, air, and water more wastes than nature can clean. So we have pollution today. To continue to survive, we must learn how to use the Earths resources wisely, without destroying them. To save the spaceship Earth, we must cooperate with nature and learn better ways to use, not to abuse our environment. Questions 20 to 22 are based on the passage you have just heard. 20. Which would be the best title for the passage？ 21. Which is true according to the passage？ 22. What can we conclude from the passage？20．

A．The present population on earth is fourteen billion.

B．Water is recycled every seventy million years.

C．The planet earth travels around the sun at 18 miles per second.

D．The earth is compared to a spaceship because they both travel around the sun.

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第5题

Daily changes in the weather affect all of us, no matter what our job or profession. Howev

er,【B1】there's very little we can do to modify the weather, we can at least know what kind of weather to expect. For this we are indebted(感激的) to our【B2】weather-watchers.

Although it may sound funny to call scientists weather-watchers, there's【B3】funny about what they do. Specifically, weather-watchers are meteorologists(气象学者)【B4】work for the United States Weather Bureau. They study the ocean of【B5】that surrounds the earth and, with the information they get, predict our weather.

The atmosphere【B6】in height from 300 to 700 miles above the earth and is divided into a series of layers or shells. The layer that is most interesting【B7】the meteorologist is the troposphere(对流层) or the layer closest to the earth.【B8】is in the troposphere that all our weather is formed.

【B9】causes our weather is really a very simple process. Endless streams of hot air push up from the earth. As they rise, they are【B10】by the freezing temperatures of the【B11】troposphere. Once it has become cold and heavy, the air【B12】back toward the earth, but it【B13】move down because of the rising hot air. In the meantime, planetary winds, which blow around the earth, or air currents keep both the cold air mass as well as the hot air mass in【B14】.

There are two additional factors that influence these moving air masses.【B15】is water vapor that the rising hot air soaks up like a sponge. The other is temperature Which, by cooling the hot air, forces it to【B16】out its water vapor in the form. of rain, snow, or sleet(雨夹雪).

These air masses【B17】push against each other with tremendous pressure. When a high-pressure mass of air succeeds【B18】pushing out a low-pressure air mass, we have clearing conditions and【B19】weather. When a low-pressure air mass forces out a high-pressure mass of air, stormy weather can be【B20】.

【B1】

A．when

B．as

C．while

D．if

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第6题

The Asian countries along the coast of the Pacific all ______ against the US new military

base in Japan.

A．came around

B．came down

C．came out

D．came up

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第7题

Smart WindowWindows not only let light in to cut down an electricity use for lighting, but

Smart Window

Windows not only let light in to cut down an electricity use for lighting, but the light coming through the window also provides heat. However, windows are not something people typically associate with being a cutting edge technology. Researchers are now working on new technologies that enable a window to quickly change from clear to dark and anywhere in between with a flip of a switch.

"It took us a long time to figure out what a window really is," says Claes Granqvist. He's a professor of solid-state physics at Uppsala University in Sweden. "It's contact with the outside world. You have to have visual contact with the surrounding world to feel well. " So, windows and natural light are important for improving the way people feel when they're stuck indoors.

Yet, windows are the weak link in a building when it comes to energy and temperature control. In the winter, cold air leaks in. When it's hot and sunny, sunlight streams in. All of this sunlight carries lots of heat and energy. And all of this extra heat forces people to turn on their air conditioners. Producing blasts of cold air, which can feel so refreshing, actually suck up enormous amounts of electricity in buildings around the world.

Windows have been a major focus of energy research for a long time. Over the years, scientists have come up with a variety of strategies for coating, glazing, and layering windows to make them more energy efficient. Smart windows go a step further. They use chromogenic technologies which involve changes of color.

Electrochromic windows use electricity to change color. For example, a sheet of glass coated with thin layers of chemical compound such as tungsten oxide works a bit like a battery. Tungsten oxide is clear when an electric charge is applied and dark when the charge is removed, that is, when the amount of voltage is decreased, the window darkens until it's completely dark after all electricity is taken away. So applying a voltage determines whether the window looks clear or dark.

One important feature that makes a smart window so smart is that it has a sort of "memory. " All it takes is a small jolt of voltage to turn the window from one state to the other. Then, it stays that way. Transitions take anywhere from 10 seconds to a few minutes, depending on the size of the window. The development of smart windows could mean that massive air conditioning systems may no longer need. "In the future," Granqvist says, "our buildings may look different. "

Which of the following statements does not indicate the importance of windows as described in the first two paragraphs？

A．Windows can change from clear to dark to save energy.

B．Windows help to save energy by letting light in.

C．Windows help to save energy by providing heat.

D．Windows enable people to have contact with the outside world.

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第8题

Our fly-away vacation have been created with American visitors in mind.

For one, we have made getting to Europe easy. Systemwide, we serve nine European cities. From New York, we fly nonstop to Paris, Frankfurt and Zurich, with continuing service to Geneva.

Second, we have designed these vacation package tours the way Americans like to travel. We have picked hotels that give you the flavor of Europe while providing real value for your money.

We Americans have always like making up our own minds. We have tours by escorted （护卫）motor coach or your own rental car. And land packages in Paris that start as low as 299—1289.

Another advantage of our fly-away vacations is that they are at a set US price. You needn’t worry about the changes in European currency. Then there is our fly-away vacation warranty. It’s your assurance that Americans stand behind your fly-away vacations.

You will find all the details of our warranty and of our European fly-away vacations in two free color brochures. Just call your travel agent or America toll-free at (800) 433-7300 to get yours.

* Restrictions：Price is valid through 10/31/88 and is per person based on double occupancy for 6 nights. Price is subject to change without notice and does not include air fare, taxes or surcharges. Hotel subject to availability on certain dates. Warranty details available upon request.

What is the best title of this passage?

A.Go shopping in Europe.

B.The beautiful scenes of Europe.

C.How to take a plane.

D.Travelling around Europe.

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第9题

听力原文： No man can change the weather. Nobody can control the weather. But if you study

correctly the signs around us we can tell important changes in weather. This way of telling what the weather will be on the following day or two is called weather forecasts.

For many centuries and in all countries people have studied the weather and tried to make weather forecasting. Sometimes distant objects such as hills and tall trees seem to be very clear and near. This is a sign of much water vapor in the air ,and therefore rain will probably come. Rings round the sun are a sign of coming rain. Many people feel pain in their bones. This is a sign of the coming of wet weather. Some birds fly high if fine weather is coming. They fly near the ground if rain or stormy weather is on the way. It is probably because of the insects which they are hunting that they fly low. If you see a rainbow during rainy weather, this is a sign that the weather will become clear and fine. Such rainbows always come in the evening. If a fog appears in the morning just about sunrise then the day will be warm. If the stars twinkle clearly at night, then fine weather will continue. If the sunset is mostly red in color, then the following day will be fine. If the rainbow appears in the morning, rainy weather will probably come. Most of the above sayings have been made by people who have used their eyes and brains to make weather forecasting.

What kind of weather will it be When distant objects such as hills and tall trees seem to be very clear and near？

A．Sunny day is coming.

B．Rain may come.

C．Fog.

D．Windy day is coming.

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