friction n. 1) [u]摩擦 [u/c]矛盾.冲突 查看更多

 

题目列表(包括答案和解析)

阅读理解

A Train Floating On Air

  A train that floats on air? It's not magic-it's magnets(磁).And it's close to reality.

  In Virginia USA the fall of 2002, a train with no wheels traveled on air and carried college students across their campus.In Japan, a whisper-quiet railway engine hovered and raced at 350 miles per hour using magnets and electricity as the power.And in China, a magnet train line linked Shanghai with nearby Pudong Airport.

  These trains use magnetic levitation(悬浮)technology, “maglev” for short.They use the same rules as the magnets you pick up at home or school:opposite poles of magnets attract each other, and like poles repel each other.

  How does it work?

  Powerful magnets on the bottom of train repel magnets on the track, which is actually just a magnet-filled guiding way.With a magnetic field of sufficient force, the train will go hovering on air, which seemed impossible to us in the past.

  When an electrical current is sent through the track, the train moves.Turn the current backwards and the train slows down.

  Maglev doesn't rely on the friction(摩擦力)of wheels on track, so it can climb a much steeper hill than a traditional train.And it can travel easily in snow and ice, something that could bring normal trains to a screaming stop.

(1)

This passage is about ________.

[  ]

A.

maglev

B.

magnets

C.

levitation

D.

electricity

(2)

Which of the following is a repelling action?

[  ]

A.

B.

C.

D.

(3)

What can we learn from the text?

[  ]

A.

A magnet-filled guiding way is formed inside a maglev train.

B.

Instead of electricity, magnets are used as the power of a maglev.

C.

Maglev trains can climb hills with the help of magnet wheels.

D.

Electric currents decide the movements of a maglev train.

(4)

What is the difference between a maglev train and an ordinary train?

[  ]

A.

A maglev train can climb mountains without power while an ordinary one can't.

B.

A maglev train can travel in college campus while an ordinary train is not allowed.

C.

Travelling without a track, a maglev train is safer and smoother than an ordinary one.

D.

Floating on a track, a maglev train is faster, quieter than an ordinary, railway train.

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阅读理解

  Possession and use of firearms are far more limited, and regulation far more stringent (严厉的) in major industrial societies other than in the United States, according to an informal survey (调查) by Washington Post correspondents. (通讯记者)

  In Germany, a person seeking to purchase (购买) a weapon not only must prove a specific need, but also must prove experience or training in the use of firearms and take a special examination in the presence of a police officer and a civilian who already is licensed. (许可)

  In Japan, with a population of 115 million, there were only 171 crimes involving the use of a gun committed in 1979. Even in Britain, whose society is fraught (充满……的) with much of the racial friction (摩擦), economic dislocation (混乱) and youth violence, crimes occur with strikingly less frequency than in America. London, with a population of 7 million, had 179 homicides last year compared to 1,557 in Los Angeles and 1,733 in New York.

  With attention in the United States focusing once again on the vexing (烦扰) issues of use and regulation of firearms following recent, widely publicized killings involving handguns, comparisons inevitably are being drawn to other industrialized, urban societies. The comparisons show a tradition abroad that varies markedly from that of the United States, one that accepts strict governmental control over possession of guns of all sorts. The laws are national in scope, strictly enforced and generally considered effective, although experts admit that illegal use of guns has been on the increase in countries such as Italy and Britain.

  In contrast to the United States, where limited federal regulations governing sales of firearms are supplemented (补充) by a crazy quilt of state laws, most other major industrial societies have uniform laws. This reflects general legal traditions in much of the rest of the world, but one other significant difference is that officials are assiduous (勤勉的) in carrying out the laws and prosecuting (起诉) offenders. (罪犯)

1.In Germany, a person cannot buy a gun if ________.

[  ]

A.he has a specific need for it

B.he has got a training in the use of gun

C.he can't find a person who is already licensed to present his examination for using gun

D.a policeman appeared when he takes his examination

2.According to the author, the main reason that the United States has a high killing rate is that ________.

[  ]

A.the United States has a large population

B.the United States is not an industrialized, urban country

C.the American society is full of racial problems

D.there are no effective laws to limit the possession and use of guns

3.Comparing to the laws in Germany and Britain, the laws in the United States are ________.

[  ]

A.more severe

B.more complete

C.in a better uniform

D.ineffective

4.Which of the following statements is NOT true?

[  ]

A.There are fewer crimes in Japan because it has small population

B.Other industrial society has very different legal traditions from the United States.

C.The officials in the United States are not competent, nor strict, when dealing with the criminals.

D.Some recent killings involving guns alarmed the American society.

5.What is the author's purpose in writing this passage?

[  ]

A.To make a comparison of the American legal traditions with those of the other industrial countries.

B.To get general statistics of killings in the United States.

C.To criticize the irresponsibility of the American officials.

D.To call for more stringent laws of limit the possession and use of firearms and more compete officials to carry them out.

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Without the friction(摩擦力)between feet and the ground, people would ________ be able to walk

[  ]

A.in no time

B.by all means

C.in no way

D.on any account

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阅读下面短文,从每题所给的四个选项中选出最佳答案.

  Henry Kissinger may be the most successful Secretary of State (国务卿) to hold that office in modern times. When he was appointed in the late 1960s, there were no American ties with Communist China.Vietnam and Berlin seemed ready to draw the United States into a third world war, and Russia was seen as the “enemy”.

  But all this has changed, and Henry Kissinger caused much of the change. In1971, he made his first trip to China, a trip that was the beginning of the present ties between the United States and China.He brought the United States and Russia closer together on major subjects by the policy he called “detente” literally meaning a relaxation. His philosophy was always to talk and to bring together. With these two policies, Kissinger did much to draw attention away from any possible Russian-American friction (摩擦). In 1973 he made his first visit to Egypt. Here he was able to begin U. S. relation with Egypt. He used this contact later to begin the sort of talks the American press called “shuttle diplomacy (穿梭外交)”. For ninety-nine days, he “shuttled” back and forth on flights between Cairo and Jerusalem to work out a step by step withdrawal (撤离) of Israeli troops from the Sinai desert. His wisdom, his careful approach to detail, and his presence made “shuttle diplomacy” work. It was the only successful approach to Mid-East peace in the thirty years since the state of Israel was founded.

   Another major work was the Strategies (战略的) Arms Limitation Talk. Though his term in office passed with the treaty unsigned, Kissinger left a draft (草案) of the treaty to which the Russians had already agreed.The SALT treaty spelled out a one-tenth reduction in nuclear arms, a great success by any standard, even if one does not consider all the other conditions and limitations included in the treaty.

    Even though he successfully helped bring an end to the Vietnam War, Kissinger's final days in office were affected, as was the entire government's branch in one way or another, by the scandals (丑闻) of the Nixon White House. Kissinger's critics (批评者们) point to his role in placing wiretaps on the phones of reporters and officials and to what they consider his “high-handed” approach to setting foreign policy. But Kissinger, during the last few months of the Nixon presidency, limited the effects of the American domestic (国内的) problems on its foreign policy. He continued talks in the Middle East. He continued close contact with the Soviet Union. History will decide in the final view, as Kissinger (and many presidents) often said, on the value of his service. Whatever they decide, whether his actions are finally to be considered wise of foolish, he had a personal vision that will be difficult to march.

(1)The main idea of the above passage is that ________.

[  ]

A.Kissinger helped smooth away the troubles of Watergate

B.Kissinger has great effect on American foreign policy

C.peace in the Middle-East would have been impossible without Kissinger

D.Kissinger helped end the cold war with Russia

(2)Kissinger's effort on the SALT treaty was most important because ________.

[  ]

A.it spelled out a one-tenth reduction in nuclear arms

B.the Russians had already agreed to it

C.it set a standard for nuclear missile (导弹) development

D.it helped stop the third world war

(3)We can conclude from the passage that ________.

[  ]

A.“shuttle diplomacy” greatly affected the SALT treaty

B.Watergate made Kissinger ineffective

C.some of the things that Kissinger began are still being worked out

D.Kissinger was not a humanitarian (人道主义者)

(4)Which of the following words best shows the author's tone in this passage?

[  ]

A.Objective.
B.Indifferent.
C.Jealous.
D.Admiring.

(5)The passage suggests that ________.

[  ]

A.Kissinger was driven by his own idea

B.Kissinger was unsuccessful in bringing about peace in the Middle East

C.Kissinger significantly changed the direction of international relationships

D.Kissinger was more important than the president during the Nixon Times

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阅读理解

  The wheel was one of man’s first inventions and yet it has also proved one of the most useful.So wide and varied are the uses of wheels, in machines and vehicles of all kinds, that it is difficult to imagine what the world would be like without them.It is surprising to hear it said, therefore, that the wheel’s importance will perhaps be greatly reduced by the end of the century(the 20th century)by an invention so new as to be still unnamed.

  The invention is a machine that floats above any surface on a cushion of air(气垫).The cushion is formed when air is blown into the bottom of the machine.This part is shaped like a saucer(碟子)turned upside down.If air is blown into this saucer, the machine rises to a height that may vary from a few inches to a few feet.

Industry is already using one form of the invention to deal with heavy loads.It can lift them with ease and since there are no wheels, and therefore no friction(摩擦),they can be put into moving with the touch of a finger.

  The new invention, however, is having a great effect on transport.Not only does it make expensive road systems unnecessary, but it enables vehicles to travel equally well over land or water.This unique(独一无二的)ability to reach most destinations has given rise to the prediction(预言)that wheeled vehicles may be as uncommon at the end of the century as aeroplanes were at the beginning.

(1)

The first paragraph tells us that ________.

[  ]

A.

a new invention may make wheels less important

B.

wide wheels have a variety of important uses

C.

the wheel’s usefulness is yet to be proved

D.

the wheel was man’s earliest invention

(2)

The passage tells us that the new invention ________.

[  ]

A.

is more important for industry than for transport

B.

makes it possible to travel without using roads

C.

will one day be used instead of aeroplane

D.

will replace wheeled vehicles in a hundred years

(3)

At the end of the century, vehicles using the new invention will probably be ________.

[  ]

A.

plentiful

B.

unimportant

C.

rare

D.

expensive

(4)

According to the passage, the new invention ________.

[  ]

A.

will soon get a name

B.

is lighter than air

C.

can go almost anywhere

D.

was uncommon a century ago

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