摘要:12.Ten years ago.the population of our village was that of theirs. A.as twice large as B.twice as large as C.twice as much as D.as twice much as

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When Geoff Marcy was 14, his parents bought him a telescope. Every night, he would go onto the roof outside his window to see the wonders of the sky.

    “What excited me most was whether there were planets in other solar systems where life might exist,” he says. “I decided to try to find planets orbiting other stars like our Sun.”

    And he did. “My fellow researcher, Paul Butler, and I found our first planet in 1995,” Dr. Marcy says. “We worked for ten years without finding anything! But we stuck with it and our patience paid off.”

    Since then, the two scientists have discovered 65 of the more than 100 planets found orbiting other stars. Dr. Marcy and Dr. Butler also spotted the first “family” of three planets. In June 2002 they announced another discovery: a Jupiter-like planet orbiting star 55Cancri.

    At first, the two researchers found only planets that orbit close to stars. Recently, the scientists found planets farther out. The planet orbiting 55Cancri is a major breakthrough: it is the first sighting of a large gas planet about same distance from the star as Jupiter is from the Sun.

    Why is this important ? Scientists think that life on Earth may exist because of two special features in our solar system. The first is Jupiter.

“Because it’s so big, Jupiter pulls comets and asteroids(小行星), or they all come and hit the Earth.” Dr. Marcy explains. “Without Jupiter , life on Earth would likely have been destroyed.”

    A second feature is that Earth is a rocky planet where liquid water, which is necessary for life , can exist. Unlike gas planets, rocky planets like Earth have surfaces where water can gather in pools and seas, which may support life. A huge space exists between the Jupiter-like planet and two other planets that lie close to 55Cancri. Is there an Earth-like planet in the space, too small for us to notice? If so, says Dr. Marcy, “We would have two striking similarities to our solar system: a Jupiter-like planet and an Earth-like planet. And there may be life!”

1.What can we learn about Dr. Marcy from the passage?

A. He is fond of watching Jupiter.

B. He is from a scientist family.

C. He dislikes working with Paul Butler.

D. He is interested in finding life in outer space.

2.Which of the following is true of the recent discovery?

A. The planet is not as protective as Jupiter.

B. The planet is close to star 55Cancri.

C. The planet proves to be a gas planet.

D. The planet is as large as Jupiter.

3.Dr. Marcy and Dr. Butler began to find new planets in ____.

A.1995       B.1985      C.2002       D.1981

4.Dr. Marcy thinks that life may exist in the 55Cancri system because ____.

A. he has found the system similar to the solar system.

B. he has discovered an Earth-like planet there.

C. he has discovered a rocky planet there.

D. he has found signs of life in the system

5.“But we stuck with it”( in Paragraph 3) means ____.

A. they felt discouraged               B. they carried on with it

C. they failed in their attempt          D. they made some progress

 

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When I first got an e-mail account ten years ago, I received communications only from family, friends, and colleagues. Now it seems that every time I check my e-mail, I have an endless series of advertisements and other correspondence that do not interest me at all. If we want e-mail to continue to be useful, we need specific laws that make spamming(发送垃圾邮件) a crime.

If lawmakers do not do something soon to prohibit spam, the problem will certainly get much worse. Computer programs allow spammers to send hundreds of millions of e-mails almost instantly. As more and more advertisers turn to spam to sell their products, individual(个人的) e-mail boxes are often flooded with spam e-mails. Would people continue to use e-mail if they had to deal with an annoying amount of spam each time?

This problem is troubling for individuals and companies as well. Many spam e-mails contain computer viruses that can shut down the entire network of a company. Companies rely on e-mail for their employees to communicate with each other. Spam frequently causes failures in their local communications networks, and their employees are thus unable to communicate effectively. Such a situation results in a loss of productivity and requires companies to repeatedly repair their networks. These computer problems raise production costs of companies, which are, in the end, passes on to the consumer.

For these reasons, I believe that lawmakers need to legislate (立法) against spam. Spammers should be fined, and perhaps sent to prison if they continue to disturb people. E-mail is a tool which helps people all over the world to communicate conveniently, but spam is destroying this convenience.

1.According to the text, what is the major cause of the flooding spam?    

A.Companies rely on e-mail for communications.

B.More people in the world communicate by e-mail.

C.More advertisers begin to promote sales through spam.

D.Many computer viruses contain spam e-mail.

2.According to Paragraph 3, who is the final victim of spam?             

A.The business

B.The advertiser

C.The consumer

D.The employee

3.What is the purpose of the text?

A.To inform

B.To educate

C.To instruct

D.To persuade

 

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