题目
题型:不详难度:来源:
Asteroids are bigger versions of the meteoroids(流星) that race across the night sky. Most orbit the sun far from Earth and don’t threaten us. But there are also thousands of asteroids whose orbits put them on a collision course with Earth.
Buy $50 million worth of new telescopes right now. Then spend $10 million a year for the next 25 years to locate most of the space rocks. By the time we spot a fatal one, the scientists say, we’ll have a way to change its course.
Some scientists favor pushing asteroids off course with nuclear weapons. But the cost wouldn’t be cheap. Is is worth it? Two things experts consider when judging any risk are: (1)How likely the event is; and (2) How bad the consequences if the event occurs. Experts think an asteroid big enough to destroy lots of life might strike Earth once every 500 000 years. Sounds pretty rare-but if one did fall, it would be the end of the world. “If we don’t take care of these asteroids, they’ll take care of us,”says one scientist. “It’s that simple.”
The cure, though, might be worse than the disease. Do we really want fleets of nuclear weapons sitting around on Earth? “The world has less to fear from doomsday(世界末日) rocks than from a great nuclear fleet set against it,” said a New York Times article.
9.What does the passage say about asteroids and meteoroids?
A.They are heavenly bodies different in composition.
B.They are heavenly bodies similar in nature.
C.There are more asteroids than meteoroids.
D.Asteroids are more mysterious than meteoroids.
10.What do scientists say about the collision of an asteroid with Earth?
A.It is very unlikely but the danger exists.
B.Such a collision might occur once every 25 years.
C.Coilisions of smaller asteroids with Earth occur more often than expected.
D.lt’s still too early to say whether such a collision might occur.
11.What do people think of the suggestion of using nuclear weapons to alter the course of asteroids?
A.It sounds practical but it may not solve the problem.
B.It may create more problems than it might slove.
C.It is a waste of money because a collision of asteroids with Earth is very unlikely.
D.Further research should be done before it is proved applicable.
12.We can conclude from the passage that .
A.while pushing asteroids off course nuclear weapons would destroy the world
B.asteroids racing across the night sky are likely to hit Earth in the near future
C.the worry about asteroids can be left to future generations since it is unlike to happen in our lifetime.
D.workable solutions still have to be found to prevent a collision of asteroids with Earth
答案
解析
10. 文章第二段后两句指出,绝大多数的小行星围绕太阳运行。远离地球,不会威胁到我们。但仍然有上千颗小行星可能撞击地球。可见,小行星与地球相撞的可能性很小,但危险确实存在。B项为概念错误。文章第三段指出,确定大多数小行星的位置需要25年。文章第五段又提到,大到足以有很强毁灭性的小行星可能每五十万年与地球碰撞一次,可见B项是错误的,C项文中没有提到,D项与文章内容不符。
11. 注意最后一段第一句中,“cure”指解决办法,即用核武器改变小行星的运行轨道,而“disease”指小行星可能与地球碰撞这件事情。由此本句可理解为核武器会比小行星带来更糟的后果,并且带给人们更大的恐慌。故选B项。
12. 应依据全文内容作出选择。全文一再强调小行星与地球碰撞的危险性,但没有提及在不久的将来会发生,故排除B项。文章最后提出对付小行星的核武器在改变小行星运行轨道的同时会毁灭地球,那么可以得出结论:解决小行星撞击地球的可行的办法有待进一步的探索。A项是事实,而不是结论。
核心考点
试题【Unless we spend money spotting and preventing asteroids(小行星) now, one might cras】;主要考察你对题材分类等知识点的理解。[详细]
举一反三
The latest project is to take a city of around half a million inhabitants and discover exactly what raw materials go into it and what go out. The aim is to find out how much of these raw materials could be provided if a plant for recycling waste were built just outside the city. This plant would recycle not only metal such as steel, lead and copper, but also paper and rubber.
Another new project is being set up to discover the best ways of sorting and separating the rubbish. When this project is complete, the rubbish will be processed like this: first, it will pass through sharp metal bars which will tear open the plastic bags in which rubbish is usually packed; then it will pass through a powerful fan to separate the lightest elements from the heavy solids; after that grounders and rollers break up everything that can be broken. Finally the rubbish will pass under magnets, which will remove the bits of iron and steel; the rubber and plastic will then be sorted out in the final stage.
The first full-scale giant recycling plants are, perhaps, fifteen years away. Indeed, with the growing cost of transporting rubbish to more distant dumps, some big cities will be forced to build their own recycling plants before long.
1. The main purpose of the passage is ________.
A. to show us a future way of recycling wastes B. to tell the importance of recycling wastes
C. to warn people the danger of some wastes D. to introduce a new recycling plant
2. How many stages are there in the recycling process?
A. 3. B. 4. C. 5. D. 6.
3. What is the main reason for big cities to build their own recycling plants?
A. To deal with wastes in a better way. B. It’s a good way to gain profits.
C. It’s more economical than to dump wastes in some distant places.
D. Energy can be got at a lower price.
4. The first full-scale huge recycling plants ________.
A. have been in existence for 15 years B. takes 15 years to build
C. can’t be built until 15 years later D. will remain functioning for 15 years
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Do you quake when your teacher says, “Now it’s time for grammar”? Do your verbs agree with your subjects?
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小题1:If a ten-year-old boy wants himself to be admired because of his speech ability, he may buy _______.
A.Word Power |
B.Word Smart Junior |
C.Grammar Smart Junior |
D.Grammar Smart: An Audio Guide to Perfect Usage |
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In discussion of technological changes, the Internet gets most of the attention these days. But the change in medicine can be the real technological event of our times. How long can humans live? Human brains were known to decide the final death. Cells are the basic units of all living things, and until recently, scientists were sure that the life of cells could not go much beyond l20 years because the basic materials of cells, such as those of brain cells, would not last forever. But the upper limits will be broken by new medicine. Sometime between 2050 and 2100, medicine will have advanced to the point at which every 10 years or so, people will be able to take medicine to repair their organs. The medicine, made up of the basic building materials of life, will build new brain cells, heart cells, and so on—in much the same way our bodies make new skin cells to take the place of old ones.
It is exciting to imaging that the advance in technology may be changing the most basic condition of human existence, but many technical problems still must be cleared up on the way to this wonderful future.
6. According to the passage, human death is now mainly caused by .
A. diseases and aging B. accidents and war
C. accidents and aging D. heart disease and war
7. In the author’s opinion, today’s most important advance in technology lies in .
A. medicine B. the Internet C. brain cells D. human organ
8. Humans may live longer in the future because .
A. heart disease will be far away from us
B. human brains can decide the final death
C. the basic materials of cells will last forever
D. human organs can be repaired by new medicine
9. How long can humans live in the future according to the passage?
A. Over 100 years. B. More than 120 years.
C. About 150 years. D. The passage doesn’t tell us.
10. We can learn from the passage that .
A. human life will not last more than 120 years in the future
B. humans have to take medicine to build new skin cells now
C. much needs to be done before humans can have a longer life
D. we have already solved the technical problems in building new cells
Studies show that during your teenage years, the body"s biological clock is reset, telling you to sleep later at night and wake up later in the morning.
But changes in the body clock aren"t the only reason teens lose sleep. Lots of people have insomnia (失眠). The most common cause of insomnia is stress. But all sorts of things can lead to insomnia. These include physical discomfort, emotional troubles and even sleeping environment. It"s common for everyone to have insomnia from time to time. But if it lasts for a month or more go and see a doctor.
Some people have a condition that causes stomach acid (酸) to move backward towards the chest. This produces the uncomfortable, burning feeling called heartburn. So even if the person doesn"t notice the feelings of heartburn because he is sleeping, he may feel tired the next day.
Most teens have nightmares sometimes. But, if they are frequent, a person"s sleep pattern can be seriously affected. The most common cause of nightmares is emotional problems, such as stress (压力) or anxiety. If you have them a lot, it"s a good idea to talk to a doctor.
Doctors encourage teens to make lifestyle changes to develop good sleeping habits. You probably know that coffee can keep you awake, but did you know that playing video games or watching TV does the same?
1. The main idea of the first paragraph is ________.
A. There is a problem that teenagers can’t get enough sleep.
B. Sleeping problems have different causes.
C. Yawning is a good way to get rid of sleep.
D. Teenagers care too much for homework.
2. The Teenagers’ biological clock ________.
A. easily makes teenagers lead to insomnia
B. is the origin of their insomnia
C. provides them with plenty of time at night
D. is helpful to improve their concentration(注意力)
3. What does the writer say about “nightmares”?
A. It is nothing and shouldn’t be taken seriously.
B. It can release their stress or anxiety.
C. Emotional problems are the only way to form nightmares.
D. People will suffer from sleep if frequent.
4. Which way can help to get rid of insomnia?
A. Drinking some coffee before going to bed.
B. Playing video game or watching TV from time to time.
C. Turning to a doctor for help.
D. Eating much medicine for insomnia.
No need, you may say, to tell that. But what I need to tell you is that you will meet with a surprising amount of opposition the moment you try to set out. Rubbish, you will reply. More people go abroad nowadays than ever before; never has travel, particularly among the young, been more strongly visit, of international exchanges. Perhaps not; but none of this, my dear young friends, is travel. Travel is not going on a round coach trip for $ 67 in all, or spending ten days at a hotel by the sea. Travel is when you want to see how much money and resources you have and then set out, alone or with chosen friends, to make an unhurried journey to a distant goal without a set date for your return.
Real travel, then, is independence in action, and is not liked by most parents. They don’t mind your going in a school party to Athens, because they know just where you are and when you’ll be back, and they can therefore permit you the imagination of freedom without for one second letting you beyond their control. But what they cannot bear is that you should travel all on your own, without giving them your address and return date. In fact, their fears are quite reasonable because that shows how much they love you. So in order to enjoy real travel and at the same time put your parents’ mind at ease. It would be really important for you to bear the following advice in mind.
5. Which statement is true according to the passage?
A. People travel more than before.
B. Young people are encouraged to travel abroad.
C. People should not go on a round coach trip for $ 67.
D. Educational visits should not be encouraged as they are not real travel.
6.What does real travel mean according to the writer?
A. It means telling your parents nothing about the travel
B. It means not knowing where you want to go.
C. It means traveling to a distant goal in an unhurried manner.
D. It means traveling without any plan.
7. Your parents allow you to travel in a school party because ________.
A. they want you to be truly free B. you are still under their control
C. they don’t have time to travel with you D. they know it’s good for you
8. According to the writer, when you do real traveling, you should ________.
A. never mind how worried your parents are
B. give your parents your address and return date
C. tell your parents details about your travel
D. not let your parents worry about you
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