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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 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 latest national survey has found that over half of China's netizens (网民) are suffering from various mental problems although some 62 percent of them claim at the same time that they are happy on the whole anyway.

This is the result of China's first White Paper on Netizens’ Health Conditions issued on Wednesday by 39.net, China's largest authoritative website on health sciences. It is the first most comprehensive health survey on netizens’ health situation ever conducted in China in ten years’ time. The white paper came out after two months of online and offline research that involved over 150 thousand netizens, covering topics and questions on health knowledge, mental situation, sense of health, and living habits.

According to the white paper, more than 70 percent of China's netizens say they are suffering from mental problems such as bad memory, anxiety, depression, and a lack of confidence. And a similar 72 percent of them also say they are often suffering from diseases like insomnia, dizziness, joint degeneration and achings. Meanwhile, another 53 percent of netizens believe that white collar employees who have bigger work pressures are more likely to catch mental problems.

The white paper adds, doing almost no sports and spending long time surfing online lead to the above mentioned health problems among netizens. Only 9 percent of netizens take up sports on weekends while over 40 percent stay home, surfing. And only 16 percent netizens can assure more than eight hours’ sleeping daily.

At present, China has a netizen population of 162 million, with a monthly consumption of 186 yuan, or about 25 dollars, on Internet surfing.

The national survey on netizens’ health situation ________.

A. was conducted on Wednesday      B. was carried out online and offline

C. is conducted every year      D. covered about half a million netizens

Which of the following has the closest meaning to the underlined part “white collar”?

A. White clothes.         B. Office workers.     

C. White offices.       D. White people.

All the following factors have been mentioned to cause the health problems among netizens EXCEPT ________.

A. shopping online         B. spending long time online

C. heavy work pressures         D. doing no sports

What’s the main idea of the passage?

A. China has a large netizen population.

B. The Internet has a negative influence on people.

C. Many netizens in China have mental problems.

D. How to surf the Internet safely and healthily.

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A study of English learning problems was carried out among a total of 106 foreign students. It shows that most students considered understanding spoken English to be their biggest problem on arrival. This was followed by speaking. Writing increased as a problem as students discovered difficulties in writing papers that they were now expected to hand in. Reading remained as a significant(显著的) problem.

The information gained helped us in determining where special attention should be paid in our course. Although many students have chosen to join the course with a reasonable motivation(动机), we considered it important to note what seemed to encourage interest. Nearly all the students have experienced some kind of grammar-based English teaching in their own country. To use the same method would be self-defeating because it might reduce motivation, especially if it has failed in the past. Therefore a different method may help because it is different.

Variety of activity was also seen as a way of maintaining(保持) or increasing motivation. Several years ago we had one timetable that operated throughout, but we soon found that both the students and the teachers lost interest by about halfway through the ten weeks. This led us to a major re-think, so finally we brought it into line with the expressed language needs of the students.

10. What is the text mainly about?

A. Foreign students have more problems.

B. There are many ways to improve English.

C. Teaching should meet students’ needs.

D. English learning problems should be studied again.

11. Writing became a bigger problem when foreign students________.

A. had to write their papers

B. became better at speaking

C. became less interested in reading

D. had fewer problems with listening

12. We may infer from the last two paragraphs that ________.

A. different teaching methods should be used

B. grammar-based teaching seems to be encouraging

C. English courses are necessary for foreign students

D. teaching content should be changed halfway.

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