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LONDON—Scientists have found an unusual way to prevent our planet from overheating: move it to a cooler spot. All you have to do is to send a few comets (彗星) in the direction of Earth, and its orbit (轨道) will be changed. Our world will then be sent moving into a safer older part of the solar system.
This idea for improving our climate comes from a group of US NASA (美国航空航天局) engineers and American astronomers. They say their plan could add another six billion years to the useful lifetime of our planet—hopefully doubling its working life.
The plan put forward by Dr. Laughlin, and his colleagues Don Korycansky and Fred Adams, needs carefully directing a comet or asteroid (小行星) so that it passes close by our planet and sends some of its gravitational energy (重力势能) to Earth.
“Earth’s orbital speed would increase as a result and we would move to a higher orbit away from the sun,” Laughlin said.
Engineers would then direct their comet so that it passed close to Jupiter (木星) or Saturn(土星). The comet would pick up energy from one of these giant planets. Later its orbit would bring it back to Earth, and the process would be repeated.
In the short term, the plan provides an ideal way to worldwide warming, although the team was actually worried about a much greater danger. The sun is certain to heat up in about a billion years and so “seriously compromise” our biosphere (生物圈)—by cooking us.
That’s why the group decided to try to save Earth.
The plan has one or two worrying sides, however. For a start, space engineers would have to be very careful about how they directed their asteroid or comet towards Earth. The smallest miscalculation (误算) in orbit could fire it straight at Earth—with deadly results.
There is also the question of the moon. As the present issue of Scientific American magazine points out, if Earth was pushed out of its present location, it is “most likely the moon would be stripped (剥离) away from Earth,” it states. This would greatly change our planet’s climate.
小题1:What makes the scientists plan to move Earth?
A.A few comets are moving to the direction of Earth.
B.Earth’s working life is coming to an end soon.
C.Earth will become too hot for mankind to keep alive.
D.The moon is moving farther and farther away from Earth.
小题2:If the plan is successful, Earth will have a working life of ________ years.
A.12 billionB.6 billionC.18 billionD.24 billion
小题3:What serious problems might the plan cause according to the passage?
A.The comet might hit Earth and man might lose the moon.
B.Earth might be moved too far away and man might die because of the coldness.
C.The comet might hit Jupiter or Saturn and never return to Earth.
D.Earth’s working life might be greatly shortened.
小题4:What does the underlined word “compromise” mean?
A.provideB.benefit (受益)C.shareD.endanger

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When I was in the eighth grade, my teacher asked us to write an article about what we would like to do when we grew up. All I could think of was one sentence I want to help other people! During the years, I met many problems. But I never gave up. I know that to help other people I have to help myself first. I encouraged myself after I experienced failures(失败). Finally .my dream really came true. I found a part-time job in a charity. I began to spend my days doing things for people. I have a happy life. That doesn’t mean that this kind of life is easy, or that my work is always enjoyable. I an happy because I an doing what I want to do.
What do you want to do? Write it down now. If you don’t know, you can ask yourself, ”What would I do if this was the last day of my  life ?” Then write down the first thing that comes to your mind, no matter(无论) how silly or impossible it is. If you have an answer, you will know what your dream is.
【小题1】The passage is developed by______.

A.space B.time C.giving an example D.giving reasons
【小题2】The writer dreams of ____.
A.having a good life B.being a rich man
C.helping others D.working for a charity
【小题3】Which of the following is TRUE?
A.The writer never have experienced failures in his dream
B.The writer could encourage himself when he’s in trouble
C.Everyone could make his dream true if he has an idea
D.No one can make his dream true
【小题4】The writer mainly wants to tell us____.
A.to believe in our dreams and never give up
B.how to help people
C.how to have a happy and easy life
D.that it is good to help other people
【小题5】The best title for the passage is___.
A.Having a Dream B.To Be with Your Dream
C.My Dream. D.Making Your Dream True.

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