17.How many things can you see in the night sky?A lot!On a clear night you might see the Moon,some planets,and thousands of sparkling stars.
You can see even more with a telescope.And with bigger and bigger telescopes you can see more and more objects in the sky.And you can see those objects in more and more detail.
But scientists believe there are some things in the sky that we will never see.We won't see them with the biggest telescope in the world,on the clearest night of the year.
That's because they're invisible.They're the mysterious dead stars called black holes.
You might find it hard to imagine that stars die.After all,our Sun is a star.Year after year we see it up in the sky,burning brightly,giving us heat and light.The Sun certainly doesn't seem to be getting old or weak.But stars do burn out and die after billions of years.
As a sta's gases burn,they give off light and heat.But when the gas runs out,the star stops burning and begins to die.
As the star cools,the outer layers of the star pull in toward the center.The star squashes into a smaller and smaller ball.If the star was very small,the star ends up as a cold,dark ball called a black dwarf (黑矮星).If the star was very big,it keeps squashing (塌缩) inward until it's packed together tighter than anything in the universe.
Imagine if the Earth were crushed until it was the size of a tiny marble.That's how tightly this dead star,a black hole,is packed.What pulls the star in toward its center with such power?It's the same force that pulls you down when you jump--the force called gravity.A black hole is so tightly packed that its gravity sucks in everything--even light.The light from a black hole can never come back to your eyes.That's why you see nothing but blackness.
So next time you stare up at the night sky,remember:there's more in the Sky han we can see!Scattered in the silent darkness are black holes--the great mystery of space.
32.According to the article,what causes a star to die?A
A.As its gases run out,it cools down.
B.It has a collision(碰撞)with other stars.
C.It can only live for about a million years.
D.As it gets hotter and hotter,it explodes.
33.Which of the following statements is NOT true?D
A.Black holes are dead stars.
B.Black holes have gravity.
C.Black holes are invisible.
D.There is nothing as mysterious as a black hole.
34.What happens AFTER a star dies?A
A.It becomes invisible.
B.It falls to Earth.
C.It gets cold with less gravity.
D.It becomes brighter and easier to see.
35.Why can't you see light when you look at a black hole?B
A.Because most black holes are so far away.
B.Because te gravity of a black hole is so strong tha it sucks the light inward.
C.Because as the star's gases burn,it stops giving off heat and light.
D.Because as a star cools,its outer layers pull in toward its center.
分析 这篇文章主要向我们介绍了一些关于宇宙中星球的天文知识.利用天文望远镜我们可以观察到太空中更多的物体,更为详细地了解星星.还有一些我们看不到的星星,它们靠气体燃烧发光,当气体燃尽,它们便成为被叫做黑洞的神秘死星.
解答 32.A 细节理解题.根据第四段的But when the gases run out,the star stops burning and begins to die.描述,可知当气体燃尽,星星便停止燃烧,我们就开始看不到它们.故选A.
33.D细节理解题.根据文章内容,They're the mysterious dead stars called black holes,黑洞是神秘的不活跃的星星,It's the same force that pulls you down when you jump--the force called gravity.黑洞上是有引力的,A black hole is so tightly packed that its gravity sucks in everything--even light.The light from a black hole can never come back to your eyes.That's why you see nothing but blackness.黑洞是看不到的,结合选项,故选D.
34.A推理判断题.根据第二段的that's because they're invisible.They're the mysterious dead stars called black holes.可知当星星成为被叫做黑洞的神秘死星后就看不见了,故选A.
35.B细节理解题.根据倒数第二段的A black hole is so tightly packed that its gravity sucks in everything-even light.The light from a black hole can never come back to your eyes.That's why you see nothing but blackness.可知,黑洞是如此紧密,它的引力吸收一切甚至是光.从黑洞发出的光永远不能回到你的眼睛.这就是为什么你看到的只是黑暗.故选B.
点评 本文是一个人生感悟类阅读理解,题目涉及多道细节理解题,做题时结合原文和题目有针对性的找出相关语句进行仔细分析,结合选项选出正确答案.推理判断题也是要在抓住关键句子的基础上合理的分析才能得出正确答案,切忌胡乱猜测,一定要做到有理有据.