Question

阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项

For more than twenty years scientists have been searching for signs of life on other planets. Most of these searches have been done over the radio. The hope is that someone in outer space may be trying to get in touch with us. Scientists also have sent radio and television messages on spaceships traveling through space, on the chance that someone may be receptive to such messages.

Scientists are using powerful radio telescopes to listen to signals from about 1, 000 stars, all within 100 light years of earth. In addition, they will scan the entire sky to “listen” for radio messages from more distant stars. Using a computer, they will be able to monitor more than eight channels at one time. Scientists are looking for any signal they stands out from the background noise.

Of the 200 billion stars in the Milky Way galaxy, scientists find that five percent are like our sun. Perhaps half of them have a planet like earth. Such a planet would be a reasonable distance from the star for temperatures to be right for the evolution of life. Based on the inhabitable（that can be lived in）planets in our galaxy, most scientists agree that chances are likely that one or more of these planets support some life.

However, many scientists wonder whether intelligent life exists on other planets. Some believe that twenty years of searching without any intelligible messages shows that no one is out there. They say that the evolution of intelligence comparable to ours is unlikely.

Other scientists believe that our search hasn’t been long enough to rule out the possibility that intelligent life exists in our galaxy. Although our sun family is only about five billion years old, our galaxy is about 20 billion years old. In that time, some scientists think it is likely that civilization much more advanced than ours have developed. Perhaps these civilizations send us no signals; perhaps we have not recognized the signals they have sent us. If we hope to find intelligent life, these scientists believe that we have to keep looking.[来

1.According to the passage, how many planets in our galaxy might be inhabitable?

A. 5 billion．            B. 10 billion.

C. 15 billion.            D. 200 billion

2.The first paragraph in this passage is mainly about ________ .

A. how scientists are looking for signs of life on other planets

B. why scientists are looking for signs of life on other planets

C. where scientists are looking for signs of life on other planets

D. when scientists are looking for signs of life on other planets

3.The underlined word “monitor” in the passage means“ ________ ”.

A. find             B. imitate

C. check              D. form

4.Which of these statements is true based on the information in the passage?

A. The earth is one of the oldest planets in our galaxy.

B. Most scientists believe that there is intelligent life on other planets.

C. Scientists are trying different ways to find signs of life on other planets.

D. Scientists don’t believe that there might be life on other planets.

Answer

1.A

2.A

3.C

4.C

【解析】

试题分析：本文讨论了人们对于外太空是否存在生命，至今为止，科学家们尝试了多种方法寻找外星生命，但都没有得到回应。也有科学家认为外太空不太可能存在生命。

1.A 数字计算题。根据第三段前两句 Of the 200 billion stars in the Milky Way galaxy, scientists find that five percent are like our sun. Perhaps half of them have a planet like earth.可知在银河系里有200billion颗恒星，其中百分之五的恒星有一颗像地球这样的行星。那么也就是10billion颗诸如地球的行星。故A正确。

2.A 段落大意题。根据本段第二句Most of these searches have been done over the radio. 和最后一句Scientists also have sent radio and television messages on spaceships traveling through space, on the chance that someone may be receptive to such messages.可知本段主要介绍的科学家们通过向太空发送无线电信号的方式来寻找外星生命。故A项正确。

3.C 词义猜测题。根据本句Using a computer, they will be able to monitor more than eight channels at one time.科学家们向太空发射无线电信号以后，使用计算机对这些信号进行监控，希望能够捕捉到外星生命的痕迹。所以该词意为“check”，故C项正确。

4.C 细节理解题。根据文章第一段Most of these searches have been done over the radio. Scientists also have sent radio and television messages on spaceships traveling through space, on the chance that someone may be receptive to such messages.可知科学家正在使用多种方法研究外星生命的存在。故C项正确。

【名师点睛】

本文5.

1．首句是主题句的规律

①给予例证、解释或说明的段落；

②下定义的段落；

③对两个或两个以上的事物作比较或对比的段落；

④表明原因和结果(往往结果交代在前)的段落。

主题句是首句的段落总是用演绎法撰写，遵循从一般到个别或特殊的写作程序，即以概述开段，随之辅以细说。这样的段落在文章中出现得最多，据专门研究阅读理论与技巧的专家们统计，概率达到70%。

2．段落尾句是主题句的规律

(1)阐述一个不常见的或难以令人接受的观点的段落。

(2)旨在说服读者相信甚至信服其论点的段落。

尾句是主题句的段落总是用归纳法撰写的，其程序是先表述细节或交代论据，最后作出概括性的结论，以总结性的句子收尾。这种写作方法的特点是从个别到一般，由特殊性到共性。

考点：考查议论文阅读