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From the first use of the rocket to carry satellites into space to the setting up of space stations，human beings have achieved many successes.But there are still numerous tasks in front of us and we should not stop trying to progress.
The international space station is an important step we should take in space exploration.It is not only helpful but also necessary.It provides a proper space environment for many experiments that we have wanted to do for a long time.It is also a base for observing the earth and the universe.It could also be an important base for later travel to the moon and Mars.In a word，if we want to explore space more，the first thing we should do is to set up a space station.
As the space station costs a lot of money，it is hard for one country alone to establish one.The US seems to be the only country that has the ability to build a space station alone，and it has tried to do so，but not very successful.So it aggregated many other countries to work on it together.Though it is still extremely expensive，it is much cheaper than doing it alone.It is really a job that needs everyone’s effort and will benefit everyone.
But even so，the funds (资金) needed are still a big problem.As for the US，it seems that it has too many things to spend its money on.Although it is the richest country in the world，it has much debt every year.It has to try to find a balance in all these issues.
1.What is the author’s attitude towards building and developing the international space station？
A. Supportive. B. Doubtful.
C. Worried. D. Reserved.
2.From Paragraph 2 we can learn that ______________.
A. the necessity of building the international space station is not realized now
B. many experiments have been done in the international space station
C. the international space station is necessary for people to explore space further
D. people have travelled to Mars from the international space station
3.Which of the following is NOT a reason for countries’cooperation in building the international space station？
A. It will benefit every participating country.
B. No country is able to build it alone.
C. It needs everyone’s effort.
D. It requires a lot of money.
4.All the following aspects about building the international space station are mentioned EXCEPT ______________.
A. difficulties B. cost
C. importance D. waste
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Ever since man began to use the telephone, there have been new problems arising from the carrying of messages. At first, each message was carried by a pair of overhead wires. As a result, telephone exchanges were soon surrounded by thousands of wires. The wires were then replaced by cables (电缆)，each containing many pairs of wires. Each cable is capable of carrying many messages. These cables, laid underground, replaced the overhead wires.
The more extensive telephone services have become, the more demand for these services has increased, particularly the demand for long-distance services. In China, for example, this growth is now over 30% every year. Long-distance telephone exchanges are usually in crowded cities, where is not easy to lay new labels for expanding services.
The use of radio to send telephone message and to link all telephone exchanges makes it possible to get rid of overhead wires and some underground cables.
Now man has invented the microwave system ( 微波系统 ). In a microwave system messages from various places can be brought together, and then they are sent out and received by radio. After that, the messages are split into their original form. Finally, they are sent to the places where they are going to be sent.
1.The word “message” ( in paragraph 1) is close in meaning to “______”.
A. electricity B. industry C. information D. wave
2.A cable is different from an overhead wire, because it ________.
A. is made of wood
B. needs more exchange
C. carries more messages
D. is much longer
3.What does the word extensive mean？
A. growing B. using C. holding D. understanding
4.The best title for the passage would be “________”.
A. The Telephone and Its Past
B. From the Wire to the Microwave System
C. The Needs for Better Telephones
D. How to Use the Telephone
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Since people first launched rockets into space in the 1950s, we have been leaving behind all sorts of things. Some of them, like the camera, were lost by astronauts while they did work outside their spacecraft. But much of the space junk is made up of little pieces of things that were once bigger objects, until they struck each other and broke apart.
Some things we send into space fall back toward Earth and burn up in the atmosphere. But larger pieces sometimes survive the extreme heat and hit the ground or the ocean at great speeds. So there is always concern that something may fall from the sky and do some harm.
But space junk falling on roofs is not the biggest worry. Scientists are concerned about the “Kessler” problem. Imagine what happens when an empty rocket strikes another while orbiting the earth. Two big things become many smaller things. They then hit other things. The pieces get smaller and smaller until they form a cloud of junk that blocks the path of future space vehicles.
Marco Castronuovo, an Italian Space Agency researcher, says launching a satellite into space that would get very close to some of the larger pieces of space junk. The satellite would connect a small rocket to the useless object. When the rocket explodes, it pushes the junk into a lower and slower orbit, nearer the Earth. After a time, the junk burns up in the atmosphere. Mr.Castronuovo has proposed using a number of small satellites with robotic arms. One arm would catch the space junk, and another arm would connect the rocket. He imagines that each satellite could jump from one large piece of junk to another. He thinks this method could destroy about ten large objects each year.
Scientists have been concerned about space junk for many years. Right now, the costs of the cleanup have been too great. Mr.Castronuovo says his system could be put in place for a much more reasonable amount of money. So what can be done to clean up the space around our planet?
1.We can learn from the text that much of the space junk ________.
A. was left by the astronauts on purpose
B. is mainly made up of broken spaceship
C. is usually made of small pieces of things
D. burns up before it reaches the atmosphere
2.Now scientists are most worried that space junk will ________.
A. harm the future space vehicles
B. do some harm to the atmosphere
C. fall on people's house roofs
D. destroy the habitat of wildlife
3.It implies in the last but one paragraph that ________.
A. clearing up the space will actually cost little
B. small rockets also do harm to the atmosphere
C. only robots can clear up the space completely
D. it is still difficult for us to clear up the space
4.What is the text mainly about?
A. Space junk threatens earth's orbital environment.
B. Scientists use different methods to clear up space junk.
C. Spacecrafts will meet with a lot of space junk in the future.
D. Marco comes up with many methods to deal with space junk.
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Anyone for rocket salad? The Chinese are now growing huge vegetables from seeds they sent into space.
If you are the type who worries about the air miles travelled by fruits and vegetables, these beauties aren’t for you. It's because they have travelled a little further than most.
The seeds from which they grew were fired into space, where they orbited the earth for two weeks. Once they returned they were grown in hothouses, producing the monster kinds seen here.
China, which is behind these space fruits and vegetables, says they could be the answer to the world's food crisis.
The 21-pound tomatoes, nine-inch chillies, 15-stone pumpkins and large watermelons growing at the Guangdong Academy of Agricultural Sciences’ hothouses can feed many more than their smaller cousins, and may have more nutrients, the scientists say.
Researcher Lo Zhigang said, "Traditional agricultural development has taken us as far as we can go and demand for food from a growing population is endless. Space seeds offer the opportunity to grow fruits and vegetables bigger and faster. "
He admitted he and his colleagues could not explain why time in orbit caused the seeds to change genetic structure. But they guessed exposure to the cosmic（宇宙的）radiation that attacked the spacecraft in orbit, as well as the near zero gravity conditions, microgravity, could play a part.
"We don't think there's any threat to human health because the genes themselves do not change; just their order changes," he said. "With genetically-modified（GM）crops you have seen environmental problems because they have added genes that can damage other organisms. But with space seeds they don't gain genes; they can only lose them. "
He also claimed the Vitamin C content in some space vegetables was nearly three times higher than in common vegetables, while levels of zinc are also increased.
Western scientists are doubtful. NASA researchers who have experimented with seeds in space say there is not enough benefit to show the cost is reasonable.
1.What do the underlined words "these beauties" in Paragraph 2 probably refer to ______?
A. Beautiful views along the air routes.
B. Travelling experiences in space.
C. Seeds fired into space.
D. Giant vegetables.
2.We can infer from Lo’s words in Paragraph 6 that _______.
A. our conventional agriculture has developed too slowly.
B. we are asking too much from nature
C. space seeds may help meet our demand for food
D. we'll grow crops in space in the future
3.Why the seeds changed their genetic structure _______.
A. remains to be proved
B. is discovered by Lo Zhigang
C. has something to do with the conditions in hothouses
D. is due to the radiation that attacked them directly
4.What can be inferred from the last paragraph?
A. Western scientists’ doubt is unreasonable.
B. Western scientists don’t believe that Chinese scientists have succeeded in the experiment.
C. Western scientists have proved space seeds to be of no benefit.
D. Western scientists think the cost of space seeds outweighs the benefits
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Anyone for rocket salad? The Chinese are now growing huge vegetables from seeds they sent into space.
If you’re the type who worries about the air miles traveled by fruits and vegetables, these beauties aren’t for you. It’s because they have traveled a little further than most.
The seeds from which they grew were fired into space, where they orbited the earth for two weeks. Once they returned they were grown in hothouses, producing the monster kinds seen here.
China, which is behind these space fruits and vegetables, says they could be the answer to the world’s food crisis.
The 21-pound tomatoes, nine-inch chilies, 15-stone pumpkins and large watermelons growing at the Guangdong Academy of Agricultural Sciences’ hothouses can feed many more than their smaller cousins, and may have more nutrients, the scientists say.
Researcher Lo Zhigang said, “Traditional agricultural development has taken us as far as we can go and demand for food from a growing population is endless. Space seeds offer the opportunity to grow fruits and vegetables bigger and faster.”
He admitted he and his colleagues could not explain why time in orbit caused the seeds to change genetic structure. But they guessed exposure to the cosmic(宇宙的) radiation that attacked the spacecraft in orbit, as well as the near zero gravity conditions, microgravity, could play a part.
“We don’t think there’s any threat to human health because the genes themselves do not change; just their order changes,” he said. “With genetically-modified(GM) crops you have seen environmental problems because they have added genes that can damage other organisms. But with space seeds they don’t gain genes; they can only lose them.”
He also claimed the Vitamin C content in some space vegetables was nearly three times higher than in common vegetables, while levels of zinc are also increased.
Western scientists are doubtful. NASA researchers who have experimented with seeds in space say there is not enough benefit to show the cost is reasonable.
72. What do the underlined words “these beauties” in paragraph 2 probably refer to?
A. Beautiful views along the air routes. B. Traveling experiences in space.
C. Seeds fired into space. D. Giant vegetables.
73. We can infer from Lo’s words in paragraph 6 that .
A. our conventional agriculture has developed too slowly
B. we are asking too much from nature
C. space seeds may help meet our demand for food
D. we’ll grow crops in space in the future
74. Why the seeds changed their genetic structure .
A. remains to be proved
B. is discovered by Lo Zhigang
C. has something to do with die conditions in hothouses
D. is due to the radiation that attacked them directly
75. Comparing Gm crops and space crops, we can see that .
A. space crops grow faster
B. space crops are more environmentally friendly
C. GM crops are less a threat to human health
D. GM crops have fewer nutrients
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Do you still remember the use we _______ the material?
| A．made of | B．made from | C．made up | D．made into |
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语法填空
Two new satellites of the BeiDou Navigation (导航) Satellite System (BDS) 1.(send) into space on a Long March－3B carrier rocket from the Xichang Satellite Launch Center in Sichuan Province，China at 2：07 a．m. on November 19，2018. The satellites entered a Medium Earth orbit 2.(safe) more than three hours later and will work with 17 other BDS－3 satellites already in space. They are also the 42nd and 43rd 3.(member) of the BDS satellite family.
China launched these satellites with 4. aim of providing navigation services for countries and regions which participate in the Belt and Road Initiative(倡议) by the end of 2018. “This is a key step for BDS developing 5. a Chinese experimental system to a regional and then a 6.(globe) navigation system，” said Yang Changfeng，chief designer of the BeiDou system. The positioning 7.(accurate) of the BDS－3 system has been improved to 2.5 meters to 5 meters，said Yang.
8.(name) after the Chinese term for the Plough，the BeiDou system has been serving China for 18 years 9. another six BDS－3 satellites will be put into the Medium Earth orbits from 2019 to 2020. The system is expected 10.(provide) first－class services around the globe by the end of 2020.
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Scientists are carrying __1._____ experiments into using spiders’ cobweb to produce __2.____(extreme ) thin wire. The research _3.____( conduct) by researchers from Germany. They have developed
__4.___process for reducing spiders’ silk _5.___about one twentieth of its normal diameter.
__6.___ is hoped that this new wire will be effective in the __7.____(grow) field of micro-electronics. They have collected data on the properties of spider silk. Their work has found evidence _8.____ the silk of the black widow spider would be the __9.____ (idea)material for the new “nanowires”. It seems even the deadly black widow can serve the cause __10.___ the scientific progress.
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_____ the drought in Southwest China, millions of people had to carry water from faraway places.
A. Due to B. In case of C. Apart from D. In spite of
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________ the drought in Southwest China, millions of people had to carry water from faraway places.
A. Apart from B. In case of C. Due to D. In spite of
__4.___process for reducing spiders’ silk _5.___about one twentieth of its normal diameter.