Question

These radio signals were heard first in 1967．They were coming from a point in the sky where there were no known stars．They were coming very regularly too：once in just about a second．It was as if they were controlled by a clock．

   The scientists who heard the signals did not tell anybody else．They were rather afraid to tell in case they frightened people．The signals were coming from a very small body—no bigger，perhaps，than the earth．Was that why no light could be seen from it? Or were the signals coming from a planet that belonged to some other star?

  There was no end to the questions．but the scientists kept the discussion secret．“Perhaps there are intelligent beings out there，”they thought，“little green men who are trying to send messages to other planets，or to us!” So the news was not given to the newspapers．Instead，the scientists studied the signals and searched for others like them．

  Well, all that happened in 1967 and 1968．Since then scientists have learned more about those strange，regular radio signals．And they have told the story，of course．The signals do not come from a planet；they come from a new kind of star called “pulsar”．About a hundred other pulsars have now been found，and most of them are very like the first one．

  Pulsars are strong radio stars．They are the smallest but the heaviest stars we know at present．A handful of pulsar would weigh a few thousand tons．Their light—if they give much light—is too small for us to see．But we can be sure of this：no little green men are living on them．

1. How was the first pulsar discovered?

    A．Scientists heard a new kind of radio signal．

    B．Scientists heard radio signals coming from an unknown star．

    C．Scientists searched the sky and saw it．

    D．Scientists heard radio signals sent by little green men from a small planet．

2.What made the scientists think that the signals might be a sign of intelligent life?

    A．Because they were coming from a very small body．possibly a planet．

    B．Because they couldn't see the body．

    C．Because it seemed that they were controlled by a clock．

    D．Because they couldn't understand the messages sent by the intelligent beings．

3.Why didn't they report the news?

    A．Because they were afraid of frightening people．

    B．Because scientists wanted to keep their discoveries secret．

    C．Because the signals were heard only once．

    D．Because they didn't know if the signals were from a pulsar．

4. When did they think it safe to report the news?

A．When everyone had forgotten the signals．

B．When the signals stopped．

C．When they were tired of studying the signals．

D．When other pulsars were discovered．

 

Answer 1

答案：B;C;A;D
解析：

1、细节理解题。从文中的描述可知，科学家收到电波之后进行研究，终于发现了其来源。 2、综合判断题。文中没有直接提到其原因，但从短文及四个选项分析，此时人们尚不知电波来自哪个 天体，也不理解其含义，但从它本身分析，文中说它每秒钟一次，有规律，仿佛用时钟控制，因此选C。 3、细节理解题。第二段直接提到原因，他们害怕告诉大家之后引起人们的恐慌。 4、推理判断题。文中没有直接提及本题内容，但说到“这一切都发生在1967、1968年”，科学家have learned…，另一百个pulsars have been found，他们have told the story，据此判断，这三者在时间上应该是一致的，因此选D。

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