Question

Unless we spend money spotting and preventing asteroids(小行星) now, one might crash into Early and destroy life as we know it, say some scientists.

Asteroids are bigger versions of the meteoroids(流星) that race across the night sky. Most orbit the sun far from Earth and don’t threaten us. But there are also thousands of asteroids whose orbits put them on a collision course with Earth.

Buy $50 million worth of new telescopes right now. Then spend $10 million a year for the next 25 years to locate most of the space rocks. By the time we spot a fatal one, the scientists say, we’ll have a way to change its course.

Some scientists favor pushing asteroids off course with nuclear weapons.  But the cost wouldn’t be cheap. Is is worth it? Two things experts consider when judging any risk are: (1)How likely the event is; and (2) How bad the consequences if the event occurs. Experts think an asteroid big enough to destroy lots of life might strike Earth once every 500 000 years. Sounds pretty rare-but if one did fall, it would be the end of the world. “If we don’t take care of these asteroids, they’ll take care of us,”says one scientist.  “It’s that simple.”

 The cure, though, might be worse than the disease. Do we really want fleets of nuclear weapons sitting around on Earth? “The world has less to fear from doomsday(世界末日) rocks than from a great nuclear fleet set against it,” said a New York Times article.

9.What does the passage say about asteroids and meteoroids?

A.They are heavenly bodies different in composition.

  B.They are heavenly bodies similar in nature.

C.There are more asteroids than meteoroids.

D.Asteroids are more mysterious than meteoroids.

10.What do scientists say about the collision of an asteroid with Earth?

A.It is very unlikely but the danger exists.

B.Such a collision might occur once every 25 years.

C.Coilisions of smaller asteroids with Earth occur more often than expected.

  D.lt’s still too early to say whether such a collision might occur.

11.What do people think of the suggestion of using nuclear weapons to alter the course of asteroids?

A.It sounds practical but it may not solve the problem.

B.It may create more problems than it might slove.

C.It is a waste of money because a collision of asteroids with Earth is very unlikely.

D.Further research should be done before it is proved applicable.

12.We can conclude from the passage that .      

A.while pushing asteroids off course nuclear weapons would destroy the world

B.asteroids racing across the night sky are likely to hit Earth in the near future

C.the worry about asteroids can be left to future generations since it is unlike to happen in our    lifetime.

D.workable solutions still have to be found to prevent a collision of asteroids with Earth

Answer 1

9-12  BABD

解析:

9. 文章第二段第一句指出，小行星是比劃過夜空的流星大的天體�？梢姸�者是性質(zhì)相同的天體，只是大小不同。

10.  文章第二段后兩句指出，絕大多數(shù)的小行星圍繞太陽運(yùn)行。遠(yuǎn)離地球，不會(huì)威脅到我們。但仍然有上千顆小行星可能撞擊地球�？梢�，小行星與地球相撞的可能性很小，但危險(xiǎn)確實(shí)存在。B項(xiàng)為概念錯(cuò)誤。文章第三段指出，確定大多數(shù)小行星的位置需要25年。文章第五段又提到，大到足以有很強(qiáng)毀滅性的小行星可能每五十萬年與地球碰撞一次，可見B項(xiàng)是錯(cuò)誤的，C項(xiàng)文中沒有提到，D項(xiàng)與文章內(nèi)容不符。

11.  注意最后一段第一句中，“cure”指解決辦法，即用核武器改變小行星的運(yùn)行軌道，而“disease”指小行星可能與地球碰撞這件事情。由此本句可理解為核武器會(huì)比小行星帶來更糟的后果，并且?guī)Ыo人們更大的恐慌。故選B項(xiàng)。

12.  應(yīng)依據(jù)全文內(nèi)容作出選擇。全文一再強(qiáng)調(diào)小行星與地球碰撞的危險(xiǎn)性，但沒有提及在不久的將來會(huì)發(fā)生，故排除B項(xiàng)。文章最后提出對付小行星的核武器在改變小行星運(yùn)行軌道的同時(shí)會(huì)毀滅地球，那么可以得出結(jié)論：解決小行星撞擊地球的可行的辦法有待進(jìn)一步的探索。A項(xiàng)是事實(shí)，而不是結(jié)論。