题目内容

Think about the different ways that people use the wind. You can use it to fly a kite or to sail a boat. Wind is one of our cleanest and richest power sources, as well as one of the oldest. Evidence shows that windmills began to be used in the ancient Iran back in the seventh century BC. They were first introduced to Europe during the 1100s, when armies returned from the Middle East with knowledge of using wind power.

For many centuries, people used windmills to grind(磨碎)wheat into flour or pump water from deep underground. When electricity was discovered in the late 1800s, people living in remote areas began to use them to produce electricity. This allowed them to have electric lights and radios. However, by the 1940s when electricity was available to people in almost all areas of the United States, windmills were rarely used.

During the 1970s, people started becoming concerned about the pollution that is created when coal and gas are burned to produce electricity. People realized that the supply of coal and gas would not last forever. Then, wind was rediscovered, though it means higher costs. Today, there is a global movement to supply more and more of our electricity through the use of wind.

1.From the text we know that windmills _______.

A. were invented by European armies

B. have a history of more than 2,800 years

C. have rarely been used since electricity was discovered

D. used to supply power to radio in remote area

2.The underlined word in Paragraph 2 probably means________.

A. making something cleaner

B. making something flow freely

C. making something flow in a particular direction

D. making something into small parts

3.One of the reasons wind was discovered in the 1970s is that_______.

A. it is one of the oldest power sources

B. wind power is cleaner

C. it was cheaper to create energy from wind

D. coal and gas failed to meet the needs

4.What would the author probably discuss in the paragraph that follows?

A. The global trend towards producing power from wind.

B. The design of wind power plants.

C. The worldwide movement to save energy.

D. The advantages of wind power.

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阅读下面短文,掌握其大意,从每题所给的四个选项(A、B、C和D)中,选出最佳选项,并在答题卡上将该项涂黑。

If you want to learn a new language, the very first thing to think about is why. Do you need it for a reason, such as your job or your studies? perhaps you’re interested in the , films or music of a different country and you know it will help a lot to have a ________of the language.

Most people learn best using a variety of ________ , but traditional classes are an ideal (理想的) start for many people. They ________ an environment where you can practice under the ________ of someone who’s good at the language. We all lead ________ lives and learning a language takes ________ . You will have more success if you study regularly, so try to develop a ________ . It doesn’t matter if you haven’t got long. Becoming fluent in a language will take years, but knowing about it takes ________ .

Many people start learning a language and soon give up. “I’m too ________ , ” they say. Yes, children do learn languages more ________ than adults,but research has shown that you can learn a language at any ________ . And learning is good for the health of your brain too. I’ve also heard people ________ about the mistakes they make when ________ . Well, relax and laugh about your mistakes ________ you’re much less likely to make them again.

Learning a new language is never ________. But with some work and devotion, you’ll make progress. And you’ll be ________ by the positive reaction of some people when you say just a few words in ________ own language. Good luck!

1.A. practical B. physical C. political D. cultural

2.A. Though B. After C. Or D. So

3.A. agriculture B. literature C. transport D. medicine

4.A. view B. form C. database D. knowledge

5.A. principles B. methods C. paintings D. computers

6.A. respect B. protect C. provide D. change

7.A. command B. guidance C. control D. pressure

8.A. simple B. busy C. normal D. happy

9.A. courage B. energy C. place D. time

10.A. habit B. project C. business D. design

11.A. a lot less B. a lot more C. some notes D. some risks

12.A. weak B. nervous C. tired D. old

13.A. privately B. quietly C. quickly D. closely

14.A. distance B. age C. speed D. school

15.A. quarrel B. think C. worry D. debate

16.A. learning B. bargaining C. singing D. working

17.A. but B. before C. if D. and

18.A. easy B. hard C. tiresome D. interesting

19.A. devoted B. deserved C. amazed D. blamed

20.A. our B. their C. your D. His

Analysis of the composition of quicksand shows that there are four key ingredients—sand, obviously water, clay and salt. Together these materials form a structure resembling a house of cards, with large water-filled gaps between the sand particles, which are loosely glued in place by the clay. As long as it’s left alone, the structure remains stable. But as soon as it’s disturbed, by stepping on it, the clay changes from a jelly-like consistency to a runny liquid. The effect is the same as stirring a pot of yoghurt. Liquefying(溶解)the clay makes the quicksand about one million times runnier, and the whole house of cards comes tumbling down, with you inside it.

Very quickly, the sand sinks to the bottom and the water floats to the top. This is where the salt comes in. When there’s enough salt present, as soon as the clay particles liquefy, electrical charges make them begin to stick together to form bigger particles and these also settle with the sand. Quicksand is a mixture which looks like solid, but behaves more like a liquid.

Despite its murderous reputation, quicksand does not such people under and swallow them, although it can hold a person in firm grip. The human body is more buoyant(有浮力) in quicksand than in water, and sooner or later anyone trapped in it will float.

Unlike most liquids, quicksand’s viscosity, or “runniness” can suddenly change if it comes under pressure, for example under a human foot. The surface gives way and the victim quickly sinks in up to the knees, surrounded by an area of dirty things that turns semi-solid around its victim. Escaping from the quicksand’s grip(紧握) requires a large amount of force. Without something solid to pull at, people often find they are stuck fast. Pulling at one leg simply makes the other one sink further.

So how do you escape from quicksand’s control? Stay still and call for help. Staying still stops you sinking any further, until--with luck--help arrives on the scene. If no one appears and you need to draw yourself out, gently lie down on your back until your body is floating on the sand. Next, roll over onto your stomach and pull yourself forwards with your hands, so that you gradually “swim” towards firmer ground. It is a slow and dirty business, but it works.

This technique has one barrier: it goes against a very powerful human nature. Faced with danger in the open, nine out of ten stay on their feet so that they can run away, in which case it can worsen the situation.

1.Which ingredient of the quicksand make someone trapped in it stuck and stuck fast?

A. Sand B. Clay C. Water D. Salt

2.From the passage we can learn that ________

A. as long as you are strong enough, you can pull yourself up from quicksand on your own

B. clay glues sand particles loosely, which makes quicksand stable, unless it is disturbed

C. because anyone trapped in quicksand will float, there is little possibility of him dying

D. looking like solid ground, quicksand is actually liquid

3.If someone is trapped in quicksand, what should he do?

A. Remain calm and wave for help

B. Stand in quicksand and get ready to run away as quickly as possible

C. “Swimming” is one of the best choices he can use to escape

D. Once in quicksand, lie down on his stomach immediately and swim slowly to safety

4. What might be the best title of the passage?

A. A human killer--quicksand

B. How to escape from danger

C. An awful experience in quicksand

D. What to do if trapped in quicksand

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