Question

  Scientists have found an unusual way to prevent our planet from overheating：move it to a cooler spot. All you have to do is send a few comets(普星)in the direction of Earth,and its or?bit will be changed. Our world will then be sent spinning into a safer, colder part of the solar system. They say their plan could add another six billion years to the useful lifetime of our planet―effectively doubling its working life.

  The plan put forward by Dr. Laughlin，and his colleagues Don Korycansky and Fred Ad?ams，needs carefully directing a comet so that it passes close by our planet and sends some of its gravitational energy 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 or Saturn. 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 global warming，although the team was actually concerned with 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)一by cooking us.

  That's why the group decided to try to save Earth.

  The plan has one or two worrying aspects, however. For a start,space engineers would have to be very careful about how they directed their comet towards Earth. The smallest miscal?culation(誤算)in orbit could fire it straight at Earth―with deadly consequences.

  There is also the question of the moon. As the current issue of Scientific American maga?zine points out，if Earth was pushed out of its current position，it is " most likely the moon would be stripped away from Earth," it states. This would greatly change our planet's climate. 

(   ) 1. The purpose of the whole plan put forward by Dr. Laughlin and his companions is to

A.     break away from the effect from the sun

B.     direct the comet to pick up energy from Jupiter or Saturn

C.     make the sun colder for human beings to live on

D.     lengthen the working life of our planet

(   ) 2. If the plan were to be successfully carried out,Earth would have a working life of
      years.

A. 6 billion B. 12 billion C. 24 billion D. 48 billion

(   ) 3. What do the last two paragraphs imply?

A.     The plan itself might put us human in danger.

B.     It is not too late to put the plan into practice.

C.     The moon means a lot to the earth and the life on it.

D.     The plan should be stopped for the safety of the earth. 

(   ) 4. What can be the best title for the passage?

A.     Earth Is in Danger

B.     How to Save the Earth

C.     Move Earth―It's No Science Fiction

D. Two Worrying Aspects We Are Faced with

Answer 1

1-4 DBAC    

A篇圍繞科學(xué)家希望通過彗星來改變地球的運行軌道從而來挽救人類的設(shè)想展開。

1. D意圖揣摩題科學(xué)家設(shè)想的最終目的是想挽救地球上的生命，包括人類自身。

2. B細(xì)節(jié)理解題通過"another six billion years to the useful lifetime of our planet―ef?fectively doubling its working life"這句話可以看出，another在這里是"另外"的意思。

3. A邏輯推理題最后兩段實際上是在討論這套方案同時給地球帶來的潛在風(fēng)險。C選項只說了一個方面，不完全，故為錯誤選項。

4. C主旨大意題全篇講了改變地球運行軌道的設(shè)想以及這樣做的影響。