Wind is the great maker of waves. There are exceptions, such as the tidal(潮汐的) waves some??times produced by earthquakes under the sea. But the waves most of us know are produced by winds blowing over the sea.

Now before constructing an imaginary life history of a typical wave, we need to know certain physical things about it. A wave has height, from trough (low point) to crest (high Point). It has length－the distance from this crest to that of the following wave. The period of the wave means the time it takes for succeeding crests to pass a fixed point. None of these things stays the same－for all depend upon the wind, upon the depth of the water and many other matters.

The water that makes up a wave does not advance with it across the sea. Each drop of water turns around in a little circle with the passing of the wave, but returns very nearly to its original position. And it is fortunate that this is so. For if the huge masses of water that make up a wave actually moved across the sea, sailing would be impossible.

If we want to find the speed of a wave, we may use the following way:

Speed = wavelength × frequency

Here, wavelength is the distance between two high points (crests), frequency means the number of cycles per second.

What causes waves?

A. Earthquakes and nothing else.         B. Only wind.

C. Wind causes most waves.                D. Wind causes some waves.

Which of the following is true according to the passage?

A. The water of a wave moves away across the sea.

B. The water of a wave remains almost at the same place.

C. The water of a wave goes with the passing of the wave.

D. The length of a wave means the distance from the top of a wave to the bottom.

The speed of Wave 1 is 100 cm/s, frequency 10. The frequency of Wave 2 is 300, while its speed is twice that of Wave 1. Which of the following is right?

A. The wavelengths of the two are equal.

B. The wavelength of Wave 1 is 10 times longer than that of Wave 2.

C. The wavelength of Wave 2 is longer than that of Wave 1.

D. The wavelength of Wave 1 is longer than that of Wave 2.

Wind is the movement of air from an area of high pressure to an area of low pressure. In fact, wind exists because the sun unequally heats the surface of the Earth. As hot air rises, cooler air moves in to fill the gap. As long as the sun shines, the wind will blow. And as long as the wind blows, people will manage it to power their lives.
Ancient sailors used sails to capture the wind and explore the world. Farmers once used windmills to grind their grains and pump water. Today, more and more people are using wind turbines to make electricity from the breeze. Over the past decade, wind turbine use has increased at more than 25 percent a year. Still, it only provides a small part of the world's energy.
Most wind energy comes from turbines that can be as tall as a 20-story building and have three 200-foot-long (60-meter-long) blades. These devices look like giant airplane propellers(螺桨)on a stick. The wind spins the blades, which turn a shaft connected to a generator.
The biggest wind turbines generate enough electricity to supply about 600 U.S. homes. Wind farms have tens and sometimes hundreds of these turbines lined up together in particularly windy spots, like along a ridge. Smaller turbines set up in a backyard can produce enough electricity for a single home or small business.
Wind is a clean source of renewable energy that produces no air or water pollution. And since the wind is free, operational costs are nearly zero once a turbine is erected. Mass production and technology advances are making turbines cheaper, and many governments decrease tax to encourage wind-energy development.
Some people think wind turbines are ugly and complain about the noise the machines make. The slowly rotating blades(螺旋风片) can also kill birds and bats, but not nearly as many as cars, power lines, and high-rise buildings do. The wind is also changeable: If it's not blowing, there's no electricity generated.
Nevertheless, the wind energy industry is increasing sharply. Globally, generation more than quadrupled(四倍) between 2000 and 2006. At the end of last year, global capacity was more than 70,000 megawatts. In the energy-hungry United States, a single megawatt is enough electricity to power about 250 homes. Germany has the most installed wind energy capacity, followed by Spain, the United States, India, and Denmark. Development is also fast growing in France and China.
Industry experts predict that if this pace of growth continues, by 2050 the answer to one third of the world's electricity needs will be found blowing in the wind
63. According to the passage, which of the following statements is true?
A. The rotating blades can kill as many birds as high-rise buildings do
B. Single families are not encouraged to build turbines.
C. The USA produces more wind power than any other country in the world.
D. The noise the turbines make may discourage people from building them.
64. The underlined word “generator” in the third paragraph probably means_______.
A. 电动机                       B. 发电机                          C. 机翼                               D. 飞机引擎
65. If the USA wants to build wind turbines in an area with 30,000 homes, how many
should they build at least?
A. 50.                                    B. 150.                                 C. 250.                                 D. 200.
66. All the following are the advantages of wind energy EXCEPT that_________.
A. it is environmentally friendly                                   B. it is free to build and operate
C. the government supports it                                              D. the energy is clean and renewable

Wind is the great maker of waves. There are exceptions, such as the tidal waves, sometimes produces by earthquakes under the sea. But the waves most of us know are produced by winds blowing over the sea.?Now before constructing an imaginary life history of a typical wave, we need to know certain physical things about it. A wave has height, from trough (low point)to crest (high point),and it has length—the distance from this crest to that of the following wave. The period of the wave means the time it takes for succeeding crests to pass a fixed point. None of these things stays the same— for all depend upon the depth of the water and many other matters.?

The water that makes up a wave does not advance with it across the sea. Each drop of water turns around in a little circle with the passing of the wave, but returns very nearly to its original position. And it is fortunate that this is so, for if the huge masses of water that make up a wave actually moved across the sea, sailing would be impossible.

If we want to find the speed of a wave, we may use the following way:

Speeding=Wavelength×Frequency

Here, wavelength is the distance between two high points (crests), frequency means the number of cycles per second.?

41.What causes waves according to the passage??

Earthquakes and nothing else.   B. Wind and volcanos.

C. Wind and earthquakes.          D. Wind and water.

42.Which of the following is true according to the text??

A. The water of a wave moves away across the sea.?

B. The water of a wave remains almost in the same place.?

C. The water of a wave goes with the passing of the wave.?

D. The length of a wave means the distance between crest and trough.

43.The underlined word “succeeding” means__________.?

A. reaching an aim    B. doing well?  C. following after   D. taking place

44.If the speed of wave 1 is 100 cm/s, and its frequency 10;and the frequency of wave 2 is 300,while its speed is twice that of wave 1.Which of the following is true??

A. The wave-lengths of the two are equal.?

B. The wave-length of wave 1 is 10 times longer than that of Wave 2.?

C. The wave-length of wave 2 is longer than that of wave 1.?

D. The wave-length of wave 1 is longer than that of wave 2.?

Wind is the great maker of waves. There are exceptions, such as the tidal waves, sometimes produces by earthquakes under the sea. But the waves most of us know are produced by winds blowing over the sea.?Now before constructing an imaginary life history of a typical wave, we need to know certain physical things about it. A wave has height, from trough (low point)to crest (high point),and it has length—the distance from this crest to that of the following wave. The period of the wave means the time it takes for succeeding crests to pass a fixed point. None of these things stays the same— for all depend upon the depth of the water and many other matters.?

The water that makes up a wave does not advance with it across the sea. Each drop of water turns around in a little circle with the passing of the wave, but returns very nearly to its original position. And it is fortunate that this is so, for if the huge masses of water that make up a wave actually moved across the sea, sailing would be impossible.

If we want to find the speed of a wave, we may use the following way:

Speeding=Wavelength×Frequency

Here, wavelength is the distance between two high points (crests), frequency means the number of cycles per second.?

41.What causes waves according to the passage??

Earthquakes and nothing else.   B. Wind and volcanos.

C. Wind and earthquakes.          D. Wind and water.

42.Which of the following is true according to the text??

A. The water of a wave moves away across the sea.?

B. The water of a wave remains almost in the same place.?

C. The water of a wave goes with the passing of the wave.?

D. The length of a wave means the distance between crest and trough.

43.The underlined word “succeeding” means__________.?

A. reaching an aim    B. doing well?  C. following after   D. taking place

44.If the speed of wave 1 is 100 cm/s, and its frequency 10;and the frequency of wave 2 is 300,while its speed is twice that of wave 1.Which of the following is true??

A. The wave-lengths of the two are equal.?

B. The wave-length of wave 1 is 10 times longer than that of Wave 2.?

C. The wave-length of wave 2 is longer than that of wave 1.?

D. The wave-length of wave 1 is longer than that of wave 2.?

Wind is the movement of air from an area of high pressure to an area of low pressure. In fact, wind exists because the sun unequally heats the surface of the Earth. As hot air rises, cooler air moves in to fill the gap. As long as the sun shines, the wind will blow. And as long as the wind blows, people will manage it to power their lives.

Ancient sailors used sails to capture the wind and explore the world. Farmers once used windmills to grind their grains and pump water. Today, more and more people are using wind turbines to make electricity from the breeze. Over the past decade, wind turbine use has increased at more than 25 percent a year. Still, it only provides a small part of the world's energy.

Most wind energy comes from turbines that can be as tall as a 20-story building and have three 200-foot-long (60-meter-long) blades. These devices look like giant airplane propellers(螺桨)on a stick. The wind spins the blades, which turn a shaft connected to a generator.

The biggest wind turbines generate enough electricity to supply about 600 U.S. homes. Wind farms have tens and sometimes hundreds of these turbines lined up together in particularly windy spots, like along a ridge. Smaller turbines set up in a backyard can produce enough electricity for a single home or small business.

Wind is a clean source of renewable energy that produces no air or water pollution. And since the wind is free, operational costs are nearly zero once a turbine is erected. Mass production and technology advances are making turbines cheaper, and many governments decrease tax to encourage wind-energy development.

Some people think wind turbines are ugly and complain about the noise the machines make. The slowly rotating blades(螺旋风片) can also kill birds and bats, but not nearly as many as cars, power lines, and high-rise buildings do. The wind is also changeable: If it's not blowing, there's no electricity generated.

Nevertheless, the wind energy industry is increasing sharply. Globally, generation more than quadrupled(四倍) between 2000 and 2006. At the end of last year, global capacity was more than 70,000 megawatts. In the energy-hungry United States, a single megawatt is enough electricity to power about 250 homes. Germany has the most installed wind energy capacity, followed by Spain, the United States, India, and Denmark. Development is also fast growing in France and China.

Industry experts predict that if this pace of growth continues, by 2050 the answer to one third of the world's electricity needs will be found blowing in the wind

63. According to the passage, which of the following statements is true?

A. The rotating blades can kill as many birds as high-rise buildings do

B. Single families are not encouraged to build turbines.

C. The USA produces more wind power than any other country in the world.

D. The noise the turbines make may discourage people from building them.

64. The underlined word “generator” in the third paragraph probably means_______.

A. 电动机                  B. 发电机                    C. 机翼                       D. 飞机引擎

65. If the USA wants to build wind turbines in an area with 30,000 homes, how many

should they build at least?

A. 50.                          B. 150.                         C. 250.                         D. 200.

66. All the following are the advantages of wind energy EXCEPT that_________.

       A. it is environmentally friendly                        B. it is free to build and operate

       C. the government supports it                                   D. the energy is clean and renewable