题目

Directions: Read the passage carefully. Fill in each blank with a proper sentence given in the box. Each sentence can be used only once. Note that there are two more sentences than you need.Many people know that trash is a big problem on planet Earth. What many people don’t know is that trash has become a problem in outer space too. 【1】Statistically, there are more than 22,000 pieces of junk in space around the earth. And these are just the items that we can see from the surface of the earth by telescopes or radars. 【2】Objects, like bits of old space rockets or satellites, move around the planet at very high speeds, so fast that even a very small piece can break important satellites or become dangerous to people, particularly astronauts. If the tiniest piece of junk crashed into a spacecraft, it could damage the vehicle. That’s because the faster an object moves, the greater the impact if the object collides with something else.To help minimize additional space junk, countries around the world have agreed to limit the time their space tools stay in orbit to 25 years. Each tool must be built to fall safely into the earth’s atmosphere, or the mass of gases that surround the earth, after that. 【3】Many scientists are also proposing different ways to clean up space junk. The Germans have been planning a space mission with robots that would collect pieces of space trash and bring them back to Earth so that they can be safely destroyed."In our opinion the problem is very challenging, and it's quite urgent as well," said Marco Castronuovo, an Italian Space Agency researcher who is working to solve the problem. 【4】 Many of these objects are tools that help people use their cell phones or computers."The time to act is now; as we go farther in time we will need to remove more and more fragments," he says.A. One reason that it’s urgent is that countries are sending more and more objects into space.B. There are also millions of smaller pieces of junk that we can’t see.C. Blowing up older satellites with a missile may create thousands of smaller pieces!D. In the upper parts of the atmosphere, it will burn up.E. When two objects in space collide, the two objects break into many smaller pieces.F. Years of space exploration have left tons of “space junk” in orbit around the planet. 答案：【答案】【1】F【2】B【3】D【4】A【解析】本文属于说明文，介绍太空垃圾越来越严重，急需解决的问题。【1】根据后一句Statistically, there are more than 22,000 pieces of junk in space around the earth.可知，数据上来看，地球周围的太空超过22000块垃圾，F选项，多年的太空探索在地球轨道上留下了数以吨计的垃圾，后一句例举了具体的数据，承接后文，切题，故选F。【2】根据前一句And these are just the items that we can see from the surface of the earth by telescopes or radars.可知，那些垃圾都是可以通过望远镜和雷达观察到的，B选项，还有很多小块垃圾我们看不清，与前一句形成对比，切题，故选B。【3】根据前一句Each tool must be built to fall safely into the earth’s atmosphere, or the mass of gases that surround the earth, after that.可知，每个发射工具必须能够安全落入地球的大气层，D选项，在地球的大气层上空，这些太空探测工具能够燃烧，陈述前一句话的结果和目的，切题，故选D。【4】根据本段第一句In our opinion the problem is very challenging, and it's quite urgent as well以及后一句Many of these objects are tools that help people use their cell phones or computers.可知，太空垃圾问题很难解决，也很紧急，A选项，紧急的原因在于人们发射了更多的卫星到太空，这些卫星主要用于帮助人们上网，讲述紧急的原因，切题，故选A。句子选择题做题技巧。做题的时候边读边做。各个问题附近的句子都需要重点阅读，圈画一些线索，再从选项中寻找相关的特征词用来判断正确答案。带入排除法也是一种很好的方法。另外，如果发现有一题拿不准的，先跳过，先做容易的能做出的题，直到读完整篇文章。至此，文章的要点和主旨、各个段落之间的逻辑关系应该基本就能清楚了。然后再回过去做之前不确定的题目。比如小题3，根据前一句Each tool must be built to fall safely into the earth’s atmosphere, or the mass of gases that surround the earth, after that.可知，每个发射工具必须能够安全落入地球的大气层，D选项，在地球的大气层上空，这些太空探测工具能够燃烧，陈述前一句话的结果和目的，切题，故选D。

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