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题目列表(包括答案和解析)

A black hole is created when a large star burns out. Like our sun, stars are unbelievably hot furnaces (熔炉) that burn their own matter as fuel. When most of the fuel is used up, the star begins to die.

The death of a star is not a quiet event. First there is a huge explosion. As its outer layer is blasted off into space, the dying star shines as brightly as a billion suns.

After the explosion gravity pulls in what’s left of the star. As the outside of the star sinks toward the center, the star gets smaller and smaller. The material the star is made of becomes tightly packed together. A star is so dense that a teaspoon of matter from it weighs billion of pounds.

The more the star shrinks, the stronger the gravity inside it becomes. Soon the star is very tiny, and the gravity pulling it in is unbelievably strong. In fact, the gravity is so strong that it even pulls light into the star! Since all the light is pulled in, none can go out. The star becomes black when there is no light. Then a black hole is born!

That’s what we know about black holes. What we don’t know is this: What happens inside a black hole after the star has been squeezed into a tiny ball? Does it keep getting smaller and smaller forever? Such a possibility is hard to imagine.

But if the black hole doesn’t keep shrinking, what happens to it? Some scientists think black holes are like doorways to another world. They say that as the star disappears from our universe, it goes into another universe. In other words a black hole in our universe could turn into a “white hole” in a different universe. As the black hole swallows light, the white hole shines brightly—somewhere else. But where? A different place, perhaps, or a different time — many years in the past or future.

Could you travel through a black hole? Right now, no. Nothing we know of could go into a black hole without being crushed. So far the time being, black hole must remain a mystery.

Black holes are a mystery—but that hasn’t stopped scientists from dreaming about them. One scientist suggested that in the future we might make use of the power of black holes. They would supply all of Earth’s energy needs, with plenty to spare. Another scientist wondered if a black hole could some day be used to swallow earthly waste—a sort of huge waste disposal(处理) in the sky!

When the star begins to die ______.

A. there is no fuel left in it                                B. its outer layer goes into space first

C. a huge explosion will happen                         D. it doesn’t give off light any longer

Which of the following doesn’t help produce a black hole?

A. The gravity inside the star is very strong.        B. The light can’t go out of the star.

C. The star becomes smaller and smaller             D. The dying star shines very brightly.

The black hole ______.

A. continues becoming smaller and smaller all the time

B. goes into another universe and becomes a white hole

C. can pull in everything we know of in the world

D. will appear at another place at a different time

What’s the best title for this passage?

A. A New Scientific Discovery: Black Holes

B. How Do Black Holes Come Into Being?

C. What Are Black Holes?

D. Travel Through A Black Hole

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    A famous foreign company that invested in China wanted to employ a reception secretary for its public relation department.

    A beautiful girl with a master degree in electric engineering became a winning candidate(候选人) through the difficult process of employment. At its last stage she faced an oral test together with another girl who was her equal not only in good looks but also in education standard. The girl we talk about was confident in herself and successful in the oral test. It seemed that she would get the chance. The examiner told her on behalf of the company that she could come to office of company next Monday as a new employee. At last he asked her, “Have you anything else to say? Shocked by the unexpected question, the beautiful girl was quite at a loss, saying with hesitation(犹豫不决),”“I have to talk with my parents before I give an answer.”Surprised, the examiner said calmly,“In that case, let’s wait till you are ready.”

    The next day the girl came to tell that her parents agreed to her beginning work next Monday. But the examiner said regretfully,“Sorry, the job position is filled by another suitable candidate. You had better have a try in another place.”The beautiful girl was surprised. She asked for an explanation and was told,“What is needed here is a person who knows her own mind.”

 That was how a good opportunity slipped away right under the nose of a beautiful girl.

What did the examiner value most?

A.One’s beautiful looks.    B.One’s knowledge.

C.One’s young age.          D.One’s independence.

It can be inferred from the passage that ________.

A.the other girl who failed at the last oral test was most likely to get the job

B.another girl chosen in next test held the company

C.the company lost its best employee

D.the examiner was surprised at his first choice

Why did the beautiful girl want to ask her parents for advice?

A.She didn’t know what to do.

B.She couldn’t answer the question.

C.She hadn’t expected the examiner would ask such a question.

D.Her parents would scold her if she agreed without their permission.

The best title of this passage probably is ________.

A.Make your decision quickly    B.Have your own judgment

C.Seize your chance in time      D.Hesitation leads to failure     

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A black hole is created when a large star burns out. Like our sun, stars are unbelievably hot furnaces(熔炉) that burn their own matter as fuel. When most of the fuel is used up, the star begins to die.

The death of a star is not a quiet event. First there is a huge explosion. As its outer layer is blasted off into space, the dying star shines as brightly as a billion suns.

After the explosion gravity pulls in what’s left of the star. As the outside of the star sinks toward the center, the star gets smaller and smaller. The material the star is made of becomes tightly packed together. A star is so dense that a teaspoon of matter from it weighs billion of pounds.

The more the star shrinks, the stronger the gravity inside it becomes. Soon the star is very tiny, and the gravity pulling it in is unbelievably strong. In fact, the gravity is so strong that it even pulls light into the star! Since all the light is pulled in, none can go out. The star becomes black when there is no light. Then a black hole is born!

That’s what we know about black holes. What we don’t know is this: What happens inside a black hole after the star has been squeezed into a tiny ball? Does it keep getting smaller and smaller forever? Such a possibility is hard to imagine.

But if the black hole doesn’t keep shrinking, what happens to it? Some scientists think black holes are like doorways to another world.They say that as the star disappears from our universe, it goes into another universe. In other words a black hole in our universe could turn into a “white hole” in a different universe. As the black hole swallows light, the white hole shines brightly — somewhere else. But where? A different place, perhaps, or a different time — many years in the past or future.

Could you travel through a black hole? Right now, no. Nothing we know of could go into a black hole without being crushed.So far the time being, black hole must remain a mystery.

Black holes are a mystery—but that hasn’t stopped scientists from dreaming about them. One scientist suggested that in the future we might make use of the power of black holes. They would supply all of Earth’s energy needs, with plenty to spare. Another scientist wondered if a black hole could some day be used to swallow earthly waste—a sort of huge waste disposal (处理) in the sky!

When the star begins to die ______.

       A.there is no fuel left in it B.its outer layer goes into space first

       C.a huge explosion will happen        D.it doesn’t give off light any longer

Which of the following doesn’t help produce a black hole?

       A.The gravity inside the star is very strong.

       B.The light can’t go out of the star.

       C.The star becomes smaller and smaller

       D.The dying star shines very brightly.

The black hole ______.

       A.continues becoming smaller and smaller all the time

       B.goes into another universe and becomes a white hole

       C.can pull in everything we know of in the world

       D.will appear at another place at a different time

What’s the best title for this passage?

       A.A New Scientific Discovery: Black Holes

       B.How Do Black Holes Come Into Being?

       C.What Are Black Holes?

       D.Travel Through A Black Hole

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A little under one-third of U.S. families have no Internet access and do not plan to get it, with most of the holdouts seeing little use for it in their lives, according to a survey released on Friday.

Park Associates, a Dallas-based technology market research firm, said 29 percent of U.S. families, or 31 million homes, do not have Internet access and do not intend to subscribe(预订) to an Internet service over the next 12 months. The second annual National Technology Scan conducted by Park found that the main reason why potential customers say they do not subscribe to the Internet is because of the low value to their daily lives rather than concerns over cost.

Forty-four percent of these families say they are not interested in anything on the Internet, versus just 22 percent who say they cannot afford a computer or the cost of Internet service, the survey showed. The answer "I'm not sure how to use the Internet" came from 17 percent of participants who do not subscribe. The response "I do all my e-commerce shopping and YouTube-watching at work" was cited by 14 percent of Internet-access refuseniks. Three percent said the Internet doesn't reach their homes.

The study found U.S. broadband adoption grew to 52 percent over 2006, up from 42 percent in 2005. Roughly half of new subscribers converted(转变) from slower-speed, dial-up Internet access while the other half of families had no prior access.

"The industry continues to chip (击破)away at the core of non-subscribers, but has a long way to go," said John Barrett, director of research at Parks Associates. "Entertainment applications will be the key. If anything will pull in the holdouts, it's going to be applications that make the Internet more similar to pay-TV," he predicted.

What does the underlined word “holdouts” in the first paragraph most probably mean?

A. some American families      

B. those who hold out one’s opinions

C. those who have been surveyed    

D. those who still haven’t access to the Internet currently

Many potential customers refuse to subscribe to the Internet mainly because __________.

A. they show too much concern about the cost

B. they can find little value of it

C. they do most YouTube-watching at work

D. the Internet doesn’t reach their homes

From the passage we can infer that _____________.

A. It is not an easy job to transform those holdouts into the Internet users

B. people will adopt dial-up Internet access no more

C. many Americans enjoy doing e-commerce shopping at home

D. more than half of the population are using the Internet in 2005

According to John Barrett, what is the key to attracting more U.S. families to broadband service?

A. making the Internet look more similar to TV set

B. applying the Internet more to entertainment

C. providing more pay-TV programs

D. chipping away at the core of non-subscribers

Which is the best title for the passage?

A. Web develops with technology

B. The present situation of web

C. Many Americans see little point to web

D. It is urgent to promote web service

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A sunflower is a sunflower. A mobile phone is a mobile phone. But can you combine the two to do something for your local environment? As early as next year it may well be possible. When you have finished with your mobile phone you will be able to bury it in the garden or a plant pot and wait for it to flower.

A biodegradable (生物可降解的) mobile phone was, this month, introduced by scientists. It is hoped that the new type of phone will encourage consumers to recycle. Scientists have come up with a new material over the last five years. It looks like any other plastic, but overtime it can break down into the soil without giving out any poisonous chemicals. British researchers used the new material to develop a phone cover that contains a sunflower seed. When this cover turns into waste, it forms nitrates (硝酸盐). These feed the seed and help the flower grow. “We’ve only put sunflower seeds into the cover so far. But we are working with plant experts to find out which flowers would perform best. Maybe we could put roses in next time.” said one scientist.

As phone technology is developing so quickly people are constantly throwing their mobiles away. This means producers are under pressure to find ways of recycling them. Some 650 million mobile phones have been sold this year. Most of them will be thrown away within two years, adding plastic, heavy metal and chemical waste to the environment. A biodegradable cover can offer some relief for nature, according to the scientists. “The seed is released and the flower grows in the pot so you don’t have to concern yourself with the phone when you have finished using it,” said Kerry Kirwan, the leader of the research team.

After you have finished using the new type of mobile phone, _______.

A. the sunflower seed will come out and flower in the pot

B. the phone cover will break down very soon in the soil

C. it will be recycled by the producers

D. it can charge itself with electricity in a green way

This type of research is done because ________.

A. the technology of making phones is changing rapidly

B. too many waste mobile phones may lead to environmental problems

C. nobody has ever thought of recycling mobile phones

D. producing mobile phones uses a lot of energy

We can infer from the story ________.

A. the new type of mobile phones are already on the market

B. the new type of mobile phones will sell extremely well

C. the material of the new type of phones is harmful

D. other flowers may be used in the new type of mobile phones

The best title of this passage is           .

A. Recycling our phones

B. The phones that flower

C. A new material for making phones

D. The harm of thrown-away phones

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