Electricity plays an essential part in our life. N...

第1题

______ electricity plays such an important part in our life ？

A.Whyisitthat

B.Whyisit

C.Whyitisthat

D.Whyisthat

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第2题

In para. 6 the author______.A．gives an example of ideal rivers for generating electricityB

In para. 6 the author______.

A．gives an example of ideal rivers for generating electricity

B．explains in detail what a suitable fiver for generating electricity should be

C．states that the amount of water in the fiver is very important

D．implies that the water plays an important role in industry

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第3题

Section II Use of English（15 minutes)Read the following text. Choose the best word（s) for

Section II Use of English

(15 minutes)

Read the following text. Choose the best word(s) for each numbered blank and mark [A] ,[B] , [C] or [D] on ANSWER SHEET1

Electricity plays an essential part in our life. No one can deny that electric light is necessary for people's life. However, can you imagine such a world where there is n0 (21) 0f electric light？ As darkness falls over, children read in the light given by oil lamps and candles. Youths (22) time only by talking instead of watching TV. Everything is surrounded by (23) shadows. (24) , we have a man named Edison. He created bulb that (25) for two days before burning out. He also developed successfully a system for (26) electricity from a central power house. It is he that gives us electric light, gramophone, moving pictures-all those we take (27) granted.

After the invention of electricity, manufacturers increasingly applied the findings of invention to their businesses, (28) generating new industrial growth. Development of electricity leads to the (29)creations of new products and materials. In the past century and a half, electricity has steadily (30) . At frist, it is scientific curiosity, then to a luxurious part of the (31), and then to being necessary in every one's life. Electricity has been common in the latest fifty years. Simple tasks, such as setting alarm clock to wake up at a (32) time or enjoying a piece of music, are accomplished via electronic means.

We live with the benefits of electricity every day. As a result, we always think that whenever we (33) 0ur gadgets into the wall socket, the power will be there. For most modern people, the loss of power means the complete loss of(34 ) Their lifestyle. is so dependent upon the grid's constancy (35) they do not know how to live without it. How do you cook a meal without electricity if your gas stove has an electric ignition？ Please imagine the life without electricity further. What do you do with a freezer full of food in a hot day？ How do you find out what is happen/ng in your area with the TV and radio off？ These are questions which should be seriously considered. Let us imagine the (36) 0f a short power outage together. Factories close down; phones and comput-ers go dead; food . (37) in refrigerators. What a disordered life that would be!

All the convenience which electricity has brought to our life should owe to Edison. When Edi-son died at his home in New Jersey in 1931, the whole United States were switched off to mark his passing, and in (38) 0f the man whose discoveries had so changed and improved the life of peo-ple everywhere. For a moment, all was (39) as the world had always been before, until Edi-

son (40) 0n the light.

21.

[A] power

[B] strength

[C] force

[D] vigor

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第4题

Electricity plays an essential part in our life. No one can deny that electric light is ne

cessary for people's life. However, can you imagine such a world where there is no【1】of electric light？ As darkness falls over, children read in the light given by oil lamps and candles. Youths【2】time only by talking instead of watching TV. Everything is surrounded by【3】shadows.【4】, we have a man named Edison. He created bulb that【5】for two days before burning out. He also developed successfully a system for【6】electricity from a central powerhouse. It is he that gives us electric light, gramophone, moving pictures—all those we take【7】granted.

After the invention of electricity, manufacturers increasingly applied the findings of invention to their businesses,【8】generating new industrial growth. Development of electricity leads to the【9】creations of new products and materials. In the past century and a half, electricity has steadily【10】. At first, it is scientific curiosity, then to a luxurious part of the【11】, and then to being necessary in every one's life. Electricity has been common in the latest fifty years. Simple tasks, such as setting alarm clock to wake up at a【12】time or enjoying a piece of music, are accomplished via electronic means.

We live with the benefits of electricity every day. As a result, we always think that whenever we【13】our gadgets into the wall socket, the power will be there. For most modern people, the loss of power means the complete loss of【14】. Their lifestyle. is so dependent upon the grid's constancy【15】they do not know how to live without it. How do you cook a meal without electricity if your gas stove has an electric ignition？ Please imagine the life without electricity further. What do you do with a freezer full of food in a hot day？ How do you find out what is happening in your area with the TV and radio off？ These are questions which should be seriously considered. Let us imagine the【16】of a short power outage together. Factories close down; phones and computers go dead; food【17】in refrigerators. What a disordered life that would be!

All the convenience which electricity has brought to our life should owe to Edison. When Edison died at his home in New Jersey in 1931, the whole United States were switched off to mark his passing, and in【18】of the man whose discoveries had so changed and improved the life of people everywhere. For a moment, all was【19】— as the world had always been before, until Edison【20】on the light.

(1)

A．power

B．strength

C．force

D．vigor

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第5题

When friends come to visit us in the evening, they spend their time telling us they are in

a hurry and looking at their watches. It isn't that our friends are all very busy; it is just that we haven't got a television. People think that we are very strange. " But what do you do in the evening？" they are always asking. The answer is very simple. Both my wife and I have hobbies. We certainly don't spend our evenings staring at the walls. My wife enjoys cooking and painting and often attends evening classes in foreign languages. This is particularly useful as we often go abroad for our holidays. I collect stamps and am always busy with my collection. Both of us enjoy listening to the music and playing chess together.

Sometimes there are power cuts and we have no electricity in the house. This does not worry us as we just light candles and carry on with what we were doing before. Our friends are lost—no television! So they don't know what to do. On such evening our house is very full as they all come to us. They all have a good time. Instead of sitting in silence in front of the television, everybody talks and plays games. Yes, life is possible without television.

The author's friends like______.

A．sitting and playing chess in the evening

B．attending classes in the evening

C．listening to music in the evening

D．watching television in the evening

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第6题

Rivers are one of our most important natural resources （资源). Many of the world&39;s grea

Rivers are one of our most important natural resources (资源). Many of the world&39;s great cities are located(坐落) on rivers, and almost every country has at least one river running through it that plays an important role in the lives of its people.

Since the beginning of the history, people have used rivers for transportation(运输). The longest one in the United States is the Mississippi. The lifeline of Egypt is the Nile. To the people of India, the Gangs is great, but it is also important for transportation; Ships can travel along it for a thousand miles. Other great rivers are the Congo in Africa and the Mekong in southeast Asia. The greatest of all for navigation (航海), however, is the Amazon in Brazil. It is so wide and so deep that large ships can go about two thousand miles upon it.

Besides transportation, rivers give food, water to drink, water for crops(庄稼), and chances for fun and entertainment for the people who live along their banks. In order to increase(增加) the supply of crops, engineers sometimes build a dam (大坝) across a river and let a lake from behind the dam. Then people can use the water not only to irrigate (灌溉) their fields but also to make electricity for their homes and industries.

However, large cities and industries that are located upon rivers often make problems. As the cities grow in size and industries increase in number, the water in the rivers becomes polluted with chemicals(化学物质) and other materials. People are learning the importance, however, of doing more to keep their rivers clean if they want to enjoy the benefits (利益) of this natural resource.

The greatest river for navigation is ___________.

A.the Amazon

B.the Nile

C.the Mekong

D.the Mississippi

From a dam, people can use the water for ___________.A.keeping the rivers clean

B.only making electricity

C.washing clothes

D.irrigation and making electricity

The water in the river is polluted because of _____________.A.people's drinking water too much

B.people's swimming in the river too much

C.chemicals and other materials

D.people's building a dam across a river

The best title of the passage is ___________.A.Rivers in Cities

B.The importance of Rivers

C.Transportation

D.Natural Resources

请帮忙给出每个问题的正确答案和分析，谢谢！

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第7题

Section BDirections: In this section, you will hear 3 short passages. At the end of each p

Section B

Directions: In this section, you will hear 3 short passages. At the end of each passage, you will hear some questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A, B, C and D.

听力原文： When friends come to visit us in the evening, they spend their time telling us that they are in a hurry and looking at their watches. It isn't that our friends are all very busy, it is just that we haven't got a television. People think that we are very strange. "But what do you do in the evening？" They are always asking. The answer is simple. Both my wife and I have hobbies. We certainly don't spend our evening staring at the walls. My wife enjoys cooking and painting and often attends evening classes in foreign languages. This is particularly useful as we always go abroad for our holiday. I collect stamps and am always busy with my collection. Both of us enjoy listening to music and playing chess together.

Sometimes there are power cuts and we have no electricity in the house. This does not worry us as we just light candles and carry on with what we were doing before. Our friends are lost--no television--so they don't know what to do. On such evenings our house is very full, as they all come over to us. They all have a good time. Instead of sitting in silence in front of the television, everyone talks and plays games. Yes, life is possible without a television.

(27)

A．They are very busy.

B．They feel tired and want to go to bed early.

C．The speaker's house has no electricity.

D．The speaker doesn't have a television set.

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第8题

How Wind Energy WorksHarnessing the wind is one of the cleanest, most sustainable ways to

How Wind Energy Works

Harnessing the wind is one of the cleanest, most sustainable ways to generate electricity. Wind power produces no toxic emissions and none of the heat trapping emissions that contribute to global warming. This, and the fact that wind power is one of the most abundant and increasingly cost-competitive energy resources, makes it a viable alternative to the fossil fuels that harm our health and threaten the environment.

The History of Wind Power

Wind power is both old and new. From the sailing ships of the ancient Greeks, to the grain mills of pre-industrial Holland, to the latest high-tech wind turbines rising over the Minnesota prairie, humans have used the power of the wind for thousands of years.

In the United States, the original heyday of wind was between 1870 and 1930, when thousands of farmers across the country used wind to pump water. Small electric wind turbines (叶轮机) were used in rural areas as far back as the 1920s, and prototypes of larger machines were built in the 1940s. When the New Deal brought grid-connected electricity to the countryside, however, windmills lost out.

Interest in wind power was reborn during the energy crises of the 1970s. Research by the U.S. Department of Energy (DOE) in the 1970s focused on large turbine designs. While these 2- and 3-MW machines proved mostly unsuccessful at the time, they did provide basic research on blade design and engineering principles. In the early 1990s, improvements in technology resulting in increased turbine reliability and lower costs of production provided another boost for wind development.

In other parts of the world, particularly in Europe, wind has had more consistent, long-term support. As a result, European countries are currently capable of meeting more of their electricity demands through wind power. Denmark, for example, already meets about 20 percent of its electricity demand from wind power. Wind generation also accounts for about six percent of the national power needs in Spain, and five percent in Germany. Serious commitments to reducing global warming emissions, local development, and the determination to avoid fuel imports have been the primary drivers of wind power development in Europe.

The Wind Resource

The wind resource how fast it blows, how often, and when plays a significant role in its power generation cost. The power output from a wind turbine rises as a cube of wind speed. In other words, if wind speed doubles, the power output increases eight times. Therefore, higherspeed winds are more easily and inexpensively captured.

Wind speeds are divided into seven classes with class one being the lowest, and class seven being the highest. A wind resource assessment evaluates the average wind speeds above a section of land (usually 50 meters high), and assigns that area a wind class. Wind turbines operate over a limited range of wind speeds. If the wind is too slow, they won't be able to turn, and if too fast, they shut down to avoid being damaged. Wind speeds in classes three (6.7 - 7.4 meters per second (m/s)) and above are typically needed to economically generate power. Ideally, a wind turbine should be matched to the speed and frequency of the resource to maximize power production.

Several factors can affect wind speed, and the ability of a turbine to generate more power. For example, wind speed increases as the height from the ground increases. If wind speed at 10 meters off the ground is 6 m/s, it will be about 7.5 m/s at a height of 50 meters. The rotors (旋翼) of the newest wind turbines can now reach heights up to 70 meters. In addition to height, the power in the wind varies with temperature and altitude, both of which affect the air density.

The more the wind blows, the more power will be produced by wind turbines. But, of course, the wind does not blow consistently all the

A．Y

B．N

C．NG

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第9题

city electricity

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第10题

Automobiles VS Public TransportPublic transport plays a central role in any efficient urba

Automobiles VS Public Transport

Public transport plays a central role in any efficient urban transport system in developing countries, where at least 16 cities are expected to have more than 12 million people each by the end of this decade, failing to give priority to public transport would be disastrous.

The term "public transport" covers many different types of vehicles, but most commonly refers to buses and trains. Rail services fall into four major categories: rapid rail (also called the underground, tube, metro, or subway), which operates on exclusive rights-of-way (优先行驶权) in tunnels or on elevated tracks; trams, which move with other traffic on regular streets; light rail, which is a quieter, more modern version of trams that can run either on exclusive rights-of-way or with other traffic: and suburban or regional trains, which connect a city with surrounding areas.

The recent trend in many cities is toward light rail over "heavy" rapid-rail systems. Whereas metros require exclusive rights-of-way, which often means building costly elevated or underground lines and stations, light rail can be built on regular city streets.

The concept of public transport also includes organized car pools, in which several people share the cost of riding together in the same private automobile. For US commuters in areas with inadequate bus and train services, this is the only "public" transport option. But even where other systems are comprehensive, there is vast potential for car pooling; recent research shows that in cities the world over, private cars during commuting hours on average carry just 1.2 1.3 persons per vehicle.

Public transport modes vary in fuel use and emissions and in the space they require, but if carrying reasonable numbers of passengers, they all perform. better than single-occupant private cars on each of these counts.

Although energy requirements vary according to the size and design of the vehicle and how many people are on board, buses and trains require far less fuel per passenger for each kilometer of travel. In the United States, for example, a light-rail vehicle needs an estimated 640 BTUs (British Thermal Units, measure of energy consumed) of energy per passenger per kilometer; a city bus would use some 690 BTUs per passenger-kilometer; and a car pool with four occupants 1,140 BTUs. A single-occupant automobile, by contrast, consumes nearly 4,580 BTUs per passenger-kilometer.

The pollution savings from public transport are even more dramatic. Since both rapid and light rail have electric engines, pollution is measured not from the motor exhaust, but from the power plant generating electricity, which is usually located outside the city, where air quality problems are less serious. For typical U.S. commuter routes, rapid rail emits 30 grams of nitrogen oxides for every 100 kilometers each rail passenger travels, compared with 43 grams for light rail, 95 grams for transit buses, and 128 grams for single-occupant automobiles. Public transport's potential for reducing hydrocarbon (碳氢化合物)and carbon monoxide(一氧化碳)emissions is even greater.

Although diesel buses—especially in developing countries—can be heavy polluters, existing technologies, such as filters, can control their exhaust. Buses can also run on less polluting fuels such as propane (丙烷, used in parts of Europe) and natural gas (used in Brazil and China). Test buses in the Netherlands that run on natural gas are estimated to emit 90 percent less nitrogen oxide and 25 percent less carbon monoxide than diesel engines do.

In addition to reducing fuel consumption and pollution, public transport saves valuable city space. Buses and trains carry more people in each vehicle and, if they operate on their own rights-of-way, can safely run at much higher speeds. In other words, they not only take up less space but also occupy it for

A．Y

B．N

C．NG

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