When you look up into the sky at night, have you ever felt that your eyes are playing tricks on (捉弄) you? It seems that the stars are moving all the time.
Actually, there is nothing wrong with your eyes. This twinkling effect is called scintillation (交光). Scintillation happens because of air movements in the earth’s atmosphere (大氣). Light is “bent (彎曲的)” when it travels through different parts of the earth’s atmosphere. As the air in the earth’s atmosphere is moving all the time, the light from the stars looks as if it is moving too.
The same thing also happens to things on the ground. On a very hot and shiny day, if you look at the road, the image in the distance is not clear and things move slightly. You can also see the same effect if you drop a rock into water. The rock appears a little unclear under the moving water.
This twinkling effect causes a lot of problems for astronomers (天文學家) since they cannot observe the stars clearly. A telescope (望遠鏡) was sent into space so that the air movements in the atmosphere could be avoided (避免). It took a long time to build the space telescope but finally in 1990, a huge space telescope called the Hubble Space Telescope was successfully sent into space. Since then, astronomers have many important observations that have helped people understand space better.
根據(jù)短文內容，選擇最佳選項。 （10分）
小題1:What happens to the light from the stars we see when the air in the earth’s atmosphere is moving?
A．It looks even brighter.
B．It looks as if it is bent.
C．It looks as if it is moving.
D．It looks like drops of rain.
小題2:Scintillation also happens on 　　　　 according to the passage.
A．rainy daysB．shiny days
C．cloudy daysD．windy days
小題3:What can you see when you drop a rock into the water?
A．The rock gets broken.
B．The rock becomes unclear.
C．The water becomes much polluted.
D．The water does not move anymore.
小題4:The underlined word “observe” means “　　　　”.
A．watchB．listenC．drawD．explain
小題5:Why is scintillation a problem for astronomers?
A．The stars never stay still.
B．It makes the stars too dark to see.
C．It makes astronomers feel too hot to work.
D．Astronomers cannot observe the stars clearly.

小題1:C
小題2:B
小題3:B
小題4:A
小題5:D

試題分析：這篇短文主要介紹了發(fā)生在大氣中的一種重要的自然現(xiàn)象——交光現(xiàn)象，短文詳細的介紹了這種現(xiàn)象的科學原理及其對宇航員工作的影響。
小題1:根據(jù)第二段As the air in the earth’s atmosphere is moving all the time, the light from the stars looks as if it is moving too.描述，可知它看起來好像在移動，故選C。
小題2:根據(jù)第三段The same thing also happens to things on the ground. On a very hot and shiny day, 描述，可知交光現(xiàn)象也可能發(fā)生在白天，故選B。
小題3:根據(jù)第三段You can also see the same effect if you drop a rock into water. The rock appears a little unclear under the moving water.描述，可知石頭變得看不清楚了。故選B。
小題4:聯(lián)系上下文，可知此處指的是，由于他們不能清楚地觀察到星星。故選A，觀察。
小題5:根據(jù)最后一段This twinkling effect causes a lot of problems for astronomers (天文學家) since they cannot observe the stars clearly. 描述，可知因此宇航員就不能清晰地觀察星星了。故選D。
點評：本文淺顯易懂，各個小題都能在文中找到適當依據(jù)。只要認真閱讀短文，注意前后聯(lián)系，就能順利完成閱讀。文章所設試題主要考察細節(jié)查找，做題關鍵是找出原文的根據(jù)，認真核查小題和原文的異同。
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