题目内容
阅读理解
The making of glass is a very old industry-at least 4, 500 years old. Glass has many extraordinary qualities and it is frequently being used in new ways. One of the most interesting new uses for glass is in telephone communication. Scientists have developed glass fibres as thin as human hair which are designed to carry light signals. When the light reaches the other end, it is first changed into electrical signals, which are in turn converted(转变) into sound messages. Called lightwave communication, the new system was used successfully in an experiment in Chicago in 1977. During the experiment two glass fibres were able to carry 672 conversations at the same time. The lightwave cable, containing 144 glass fibres, has the capacity(容量) to carry 50,000 conversations at the same time. The lightwave communication system has two important advantages. First the glass fibre cables are smaller and weigh less than copper(铜) cables; second, they cost less.
1.One of the extraordinary qualities of glass is that it can carry ________.
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2.Before you can hear a message on the telephone using the new system ________.
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A.the light signals have to be Changed into electrical sound
B.neither the light nor the electrical signals have to be changed in any way
C.light must first be changed into electrical signals and then into sound
D.electrical signals must first be changed into light signals and then into sound
3.According to the passage the new telephone communication system
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A.was put on experiment in 1977
B.had been put into actual use by 1977
C.had been repeatedly experimented before 1977
D.was first put into actual use in 1977
4.From the passage, you can tell that people prefer glass fibre cables to copper cables because ________.
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A.glass fibre is easier to make
B.glass fibre is less expensive
C.glass fibre is more up to date
D.glass fibre delivers messages directly
5.Which of the following statements best expresses the main idea of the passage?
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A.Light signals have changed the use of glass in industry.
B.Glass fibres have reduced the cost of telephone communication.
C.Glass is very useful because it has many unusual qualities.
D.The use of glass fibres to carry telephone messages is an interesting new development.
解析:
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1.B 由“Scientists have developed glass fibres as thin as human hair which are designed to carry light signals.”可知。 2.C 由“When the light reaches the other end, it is first changed into electrical signals, which are in turn converted(转变) into sound messages.”可知。 3.A 由“…the new system was used successfully in an experiment in Chicago, in 1977.”可知。 4.B 由“…second,they cost less.”可知。 5.D 由“Glass has many extraordinary qualities and it is frequently being used in new ways.”可知。 |
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