题目内容
A black hole is a place in space where gravity pulls so much that even light cannot get out. The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star is dying.
Because no light can get out, people can’t see black holes. Space telescopes with special tools can help find black holes. The special tools can see how stars that are very close to black holes act differently from other ones.
Black holes can be big or small. Scientists think the smallest black holes are as small as just one atom. These black holes are very tiny but have the mass of a large mountain. Mass is the amount of matter, or “staff”, in an object.
Another kind of black hole is called “stellar”(星球黑洞). Its mass can be up to 20 times more than the mass of the sun. There may be many stellar mass black holes in Earth’s galaxy. Earth’s galaxy is called the Milky Way.
The largest black holes are called “supermassive”(超大质量黑洞). These black holes have masses that are more than one million suns together. Scientists have found proof that every large galaxy contains a supermassive black hole at its center. The supermassive black hole at the center of the Milky Way galaxy has a mass equal to about four million suns and would fit inside a very large ball that could hold a few million Earths.
Scientists think the smallest black holes formed when the universe began. Stellar black holes are made when the center of a very big star falls in upon itself, or falls apart. When this happens, it exploded part of the star into space. Scientists think supermassive black holes were made at the same time as the galaxy they are in.
A black hole can not be seen because strong gravity pulls all of the light into the middle of the black hole. But scientists can see how the strong gravity affects the stars and gas around the black hole. Scientists can study stars to find out if they are flying around, or orbiting a black hole.
When a black hole and a star are close together, high-energy light is made. This kind of light cannot be seen with human eyes. Scientists use satellites and telescopes in space to see the high-energy light.
1. The gravity of a black hole may become so strong that light cannot get out when ____________.
A. the star is going to die
B. special tools are used on it
C. other stars come close to it
D. it is seen from the space telescopes
2. According to the passage, which of the following is NOT true?
A. A black hole can be very tiny but extremely heavy.
B. The gravity of a black hole holds all light in its center.
C. Scientists observe high-energy light through their own eyes.
D. Some small black holes came into being as early as the universe.
3. Which can be inferred from the passage?
A. Every galaxy must have a black hole.
B. A galaxy is the center of the universe.
C. A galaxy consists of a large group of stars and planets.
D. Earth’s galaxy is called the Milky Way.
4. What does the last sentence in Paragraph 5 suggest?
A. Neither the sun nor the earth is as heavy as a black hole.
B. There is only one supermassive black hole at the center of the Milky Way.
C. The supermassive black hole had existed before the Milky Way was formed.
D. There is a reason why the large black holes are called “supermassive”.
5. The last two paragraph mainly focus on the question of _________.
A. what a black hole is
B. how black holes form
C. how big black holes are
D. how scientists know about black holes
1.A
2.C
3.C
4.D
5.D
【解析】
试题分析: 本文是一篇科普性知识短文,在文中作者介绍了黑洞的形成,它的特点以及科学家探索研究黑洞的方法。科学家认为最小的黑洞在宇宙开始时形成的,这些黑洞可能会非常小,但是却有一座山一样的质量。而且根据文章我们可以了解到黑洞的不可见是因为强大的引力将所有的光线吸进黑洞中间的缘故。
1.
2.
3.
4.
5.。最后两段内容中提到虽然黑洞不能被看到,但是科学家们可以通过太空望远镜和卫星可以对黑洞进行研究,由此可知在这两段作者介绍科学家是如何找到黑洞的,故选D。
考点:考查科普教育类阅读
假如你叫李华,现正在美国加利福尼亚州上大学,你的一个朋友刘英写信向你了解美国加利福尼亚州的情况,请根据以下内容提示给他回信简介加利福尼亚州。
地理方面 | 面积42.4万平方千米,美国西部,西濒太平洋,美国面积第三大的州 |
人口方面 | 约38,000,000人; 据说15000前印第安人首先进入;16世纪欧洲人开始进入;19世纪中世界各地的人带着发财梦进入;未来将还会有人因喜爱加州的气候和生活方式进入。 |
语言方面 | 58% 的人把英语作为母语来讲,42%的人讲其它语言。 |
加利福尼亚州: California;太平洋:the Pacific;印第安人:Indians
【写作内容】
请根据以上内容给朋友写回信,内容包括:
1、加里福尼亚的地理方面的信息;
2、人口及其语言方面的信息;
3、信的开头和结尾已经给出,不计入句子数。
【写作要求】
只能用5个句子表达全部内容。
【评分标准】
句子结构准确,信息内容完整,篇章连贯。
Dear Liu Ying,
Your letter reached me yesterday. You would like me to tell you something about California, so now I am writing to you.
If you want to know more, you may go to https://en.wikipedia.org/wiki/California#History.
Best wishes to you.
Yours ever,
Li Hua