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Before you can hear a message on the telephone using the new system, ______.A．electrical s

Before you can hear a message on the telephone using the new system, ______.

A．electrical signals must first be changed' into light signals and then into sound

B．the light signals have to be changed directly into sound

C．light must first be changed into electrical signals and then into sound

D．neither the light nor the electrical signals have to be changed in any way

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更多“Before you can hear a message …”相关的问题

第1题

Tom had once worked in a city office in London, but now he is out of work. He had a large

family to support, so he often found himself in difficulty. He often visited Mr. White on Sundays, told him about his troubles, and asked for two or three pounds. Mr. White, a man with a kind hear(, found it difficult to refuse the money, though he himself was poor. Tom had already received more than thirty pounds from Mr. White, but he always seemed to be in need of some more.

One day, after telling Mr. White a long story of his troubles, Tom asked for five pounds.

Mr. White had heard this sort of thing before, but he listened patiently to the end. Then he said, "I understand your difficulties, Tom. I' d like to help you. But I' m not going to give you five pounds this time. I'll lend you the money, and you can pay me off next time you see me."

Tom took the money, but he never appeared again.

Tom was now in difficulties because he ______.

A．worked in a city office and was poorly paid

B．was poorly paid and had a large family to support

C．was poorly paid and always spent money carelessly

D．was out of work and had a large family to support

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第2题

The sense of sound is one of our most important means of knowing what is going on around u

s. Sound has a waste product, too, in the form. of noise. Noise has been called unwanted sound. Noise is growing and it may get much worse before it gets any better.

Scientists, for several years, have been studying how noise affects people and animals. They are surprised by what they have learned. Peace and quiet are becoming harder to find. Noise pollution is a threat that should be looked at carefully.

There is a saying that it is so noisy that you can't hear yourself think. Doctors who study noise believe that we must sometimes hear ourselves think. If we don't, we may have headaches, other aches and pains, or even worse mental problems.

Noise adds more tension to a society that already faces enough stress.

But noise is not a new problem. In ancient Rome, people complained so much about noise that the government stopped chariots(战车) from moving through the streets at night!

Ways of making less noise are now being tested. There are even laws controlling noise. We cannot return to the "good old days" of peace and quiet. But we can reduce noise—if we shout loudly enough about it.

Why are scientists surprised by the findings in their noise study？

A．Because the world is becoming increasingly noisy.

B．Because they have learned that noise is also is also a kind of pollution.

C．Because noise is an unwanted waste for human beings.

D．Because people knew little about noise before.

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第3题

Learning how to write is like taking a course in public speaking. I ’d ask whether anyone

in class had ever taken such a course. Invariably a few hands would go up.

“What did you learn in that course？” I’d ask.

“Well, the main thing was learning how to face an audience, not to be inhibited (拘谨；抑制), not to be nervous, ”

Exactly, when you take a course in public speaking nowadays, you don’t hear much about grammar and vocabulary. Instead, you’re taught how not to be afraid or embarrassed, how to speak without a prepared script, how to reach out to the live audience before you. Public speaking is a matter of overcoming your longstanding nervous inhibitions.

It is the same in writing. The point of the whole thing is to overcome your nervous inhibi- tions, to break through the invisible barrier that separates you from the person who’ll read what y- ou wrote. You must learn to sit in front of your typewriter or dictating machine and reach out to the person at the other end of the line.

Of course, in public speaking, with the audience right in front of you, the problem is easier. Y ou can look at them and talk to them directly. In writing, you ’re alone. It needs an effort of your experience or imagination to take hold of that other person and talk to him or her. But that effort is necessary or at least it’s necessary until you’ve reached the point when you quite naturally and unconsciously “talk on paper.”

The main task of a public speech course is to ________.

A.teach spoken-language experience

B.teach how to use gestures to assist speech

C.help the learners overcome nervousness

D.teach how to control the volume of the speaker’s voice

Learning how to write is similar to learning how to speak in public in that a writer should ___________.A.overcome his or her nervousness in the first place

B.watch his or her grammar and vocabulary

C.collect a lot of data before writing

D.take hold of a reader and talk to him or her before writing

In the author’s opinion_________.A.writing needs more experience and skill than public speaking

B.both writing and public speaking require effort

C.writing is imaginative

D.public speaking is not so natural as writing

Which of the following statements is TRUE according to the passage？A.Not many students feel the need to learn public speaking

B.Training is necessary before you can speak with script

C.In public speaking, the audience are more nervous than the speaker

D.Writing is just like making a public speech on paper

This selection is mainly about learning how to _______.A.make a public speech

B.talk on paper

C.behave properly in public speech

D.express strong emotion on paper

请帮忙给出每个问题的正确答案和分析，谢谢！

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第4题

The sense of sound is one of our most important means of knowing what is going on around u

s. Sound has a waster product, too, in the form. of noise. Noise has been called unwanted sound. Noise is growing and it may get much worse before it gets any better.

Noise adds more tension (紧张) to a society that already faces enough stress.

But noise is not a new problem. In ancient Rome, people complained so much about noise that government stopped chariots (四轮马车) from moving through the streets at night!

Ways of making less noise are now being tested. There are even laws controlling noise. We cannot return to the "good old days" of peace and quiet. But we can reduce noise--if we shout loudly enough about it.

Why are scientists surprised by the findings in their noise study？

A．Because the world is becoming more and more noisy.

B．Because they have learned that noise is also a kind of pollution.

C．Because noise is an unwanted waste for human beings.

D．Because people knew little about noise before.

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第5题

Listen! __Ican hear a cat（）

A.an you hear a cat

B.What is it

C.What can you hear

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