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”(超大質量黑洞). 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.
小題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
小題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.
小題3:The underlined word “galaxy” in Paragraph 5 means __________.
A.a(chǎn) black holeB.the Milky Way
C.a(chǎn) series of starsD.a(chǎn) planet near the earth
小題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 a 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”.
小題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

小題1:A
小題2:C
小題3:C
小題4:D
小題5:D

試題分析:文章介紹黑洞的形成,它的特點以及科學家探索研究黑洞的方法。
小題1:細節(jié)題:根據(jù)文章第一段中“This can happen when a star is dying.”可知恒星的死亡可能會形成黑洞。故選A。
小題2:細節(jié)題:根據(jù)第三段中“These black holes are very tiny but have the mass of a large mountain”這些黑洞可能會非常小,但是有一座山一樣的質量,可知A正確;根據(jù)倒數(shù)第二段中“A black hole can not be seen because strong gravity pulls all of the light into the middle of the black hole.”黑洞不可見是因為強大的引力將所有的光線吸進黑洞的中間,可知B項正確;根據(jù)最后一句“Scientists use satellites and telescopes in space to see the high-energy light.”科學家們使用衛(wèi)星和太空望遠鏡查看高能光,可知科學家不是用自己的眼睛,因此C錯誤;根據(jù)第六段中“Scientists think the smallest black holes formed when the universe began.”科學家認為最小的黑洞在宇宙開始時形成,可知D項正確。故選C。
小題3:推理題:根據(jù)第四段中“Earth’s galaxy is called the Milky Way”地球所在的星系叫銀河系,常理可知星系是有很多星星組成的。故選C。
小題4:推理題:根據(jù)第五段最后一句“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.”在銀河系中心的超大質量黑洞的質量相當于四百萬個太陽,是一個可以容納幾百萬地球在內的巨大的球,由此可知這是在解釋什么叫做“超大質量黑洞”。故選D。
小題5:推理題:閱讀最后兩段內容可知是在介紹科學家是如何找到黑洞的。故選D。
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D.Stay in a comfortable and quiet place.
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B.children liking to watch TV
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小題1:What is Paragraph 2 mainly about?
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B.Bees are important in food crops.
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D.Cherry trees are pollinated by bees.
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C.Large insects.D.Some virus.
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C.Only researchers in California want to know what kills bees.
D.Large animals are easier to study than tiny insects.

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科目:高中英語 來源:不詳 題型:閱讀理解

Julie was preparing for a trip when her phone slipped into a sink full of water. Panic moment! She quickly picked up the wet phone and tried to turn it on, but nothing worked. Her first reaction? She got dressed, drove to the nearest store, and bought a new model at full price.
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Fortunately, there’s a solution.
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Do you go to unusual lengths to make sure you have your phone? That’s another sign of a problem. If you find you check your phone plenty of times per hour, or a total of an hour per day, there may be a problem.
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B.To introduce the topic for discussion.
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C.Eagerness for new mobile phones.
D.Independence of mobile phones.
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A.Avoiding using phone for some time
B.Learning more about modern technology.
C.Protecting one’s phone against any damage.
D.Not using a mobile phone in one’s daily work.
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A.It lets you know other people also lose their phones.
B.It will give you a new phone through insurance.
C.It enables you to reconnect with your acquaintance.
D.It gives you a prescription to treat nomophobia.
小題5: What is the passage mainly about?
A.Solutions to nomophobia.B.New mobile phone technology.
C.Disadvantages of mobile phone.D.Attitude toward mobile phone.

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