Question

If you look at the sky one night and see something moving and shining that you have never seen before, it might be a comet （彗星）．

A comet sometimes looks like a star．Like a planet, a comet has no light of its own．It shines from the sunlight it reflects （反射）．Like the earth, a comet goes round the sun, but on a much longer path （轨道） than the earth travels．

If a comet isn’t a star, what is it then?

Some scientists think that a large part of a comet is water frozen into pieces of ice and mixed with iron and rock dust and perhaps a few big pieces of rock．When sunshine melts （融化） the ice in the comet, great clouds of gas go trailing after it．These clouds, together with the dust, form a long tail．

Many people perhaps have seen a comet．However no one knows how many comets there are．There may be millions of comets, but only a few come close enough for us to see．

An Englishman named Edmund Halley, who lived from 1656 to 1742, found out a lot about the paths that comets take through the sky．Some comets move out of our sight and never come back．Others keep coming back at regular times．A big comet that keeps coming back was named after Halley because he was the one who worked out when it would come back again．Maybe you have ever seen Halley’s Comets because the last time it came close to the sun and the earth was in the year 1986．Then people all over the world were outside at night to look at it．You will probably be able to see Halley’s Comets when it comes near the earth again．

1.A comet is like ________．

A．sun  B．moon  C．sunlight  D．the earth

2.A large part of a comet is ______．

A．water and rock

B．water frozen into pieces of ice and mixed with iron

C．ice, iron and rock dust

D．only a few big pieces of rock

3.Maybe many people _______．

A．haven’t seen any comets       B．have seen all comets

C．have seen a comet at daytime   D．have seen a comet

4.Some comets keep coming back ________．

A．at any time  B．at noon

C．at regular times  D．at daytime

5.Halley’s Comets came back _____．

A．in 1990  B．in 1980  C．in 1986  D．in 1989

Answer

1.D

2.B

3.D

4.C

5.C

【解析】

试题分析：这篇短文介绍了彗星的情况，它不发光，但是它反射光，有一个彗星叫Halley，当它离地球最近的时候，人们可以看见它。

1.D细节理解题。根据短文第二段第二行“Like the earth”可知，故选D。

2.B细节理解题。根据短文第四段第一行“ a large part of a comet is water frozen into pieces of ice and mixed with iron”可知。故选B。

3.D细节理解题。根据短文倒数第二段第一行“Many people perhaps have seen a comet．”这里perhaps和maybe是同义词译为“也许”二者是同意句，故选D。

4.C细节理解题。根据短文最后一段第二行“Others keep coming back at regular times”可知．故选C。

5.

考点：科普类短文阅读。