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东北农业大学网络教育学院
大学英语第三册作业题（2014更新版）
一、单项选择题
1. He is watching TV? He is _____ to be cleaning his room.
A) known B) supposed C) regarded D) considered
2. The Smiths decided to _____ a boy and a girl though they already had three children.
A) adapt B) bring C) receive D) adopt
3. The newspaper didn’t mention the ___ of the damage caused by the fire.
A) range B) level C) extent D) quantity
4. We can not trust him any more because he often ________ his duty.
A) owes B) spoils C) deserts D) neglects
5. In order to increase our output, we need to import more production _______.
A) facilities B) hens C) votes D) artists
6. Free medical service is _______ to nearly all the college students in China.
A) favorite B) available C) convenient D) average
7. Iron supplements may produce a feeling of wanting to ____ , and may be poisonous in some cases.
A) throw away B) throw up C) throw in D) throw out
8. Grant Wood instantly ____ to fame in 1930 with his painting American Gothic, an often-copied interpretation of the solemn pride of American farmers.
A) arise B) rise C) rose D) raised
9. James Montgomery is famous for his army ____ posters of World Wars I and II.
A) recruited B) recruiting C) recruit D) recrutation
10. If you had been ____ in your study, you would have passed the examination without any difficulty.
A) big-minded B) single-minded C) broad-minded D)narrow-minded
11. My English professor told me to____ my vocabulary, to ____ my sentence length and to ____ my tone.
A) amplify; justify; enlarge B)enlarge; justify; diversify
C) diversify; enlarge; amplify D) enlarge; amplify; diversify
12. The Buffalo nickel was ____ in memory of the destruction of the buffalo herds and the American Indians.
A) descended B) designed C) deprived D) detailed
13. The point in ____ by correspondence is not whether we should do it but whether we can do it.
A) argument B) debate C) dispute D) controversy
14. ____ their difference, the couple were developing an obvious and genuine affection for each other.
A) But for B) For all C) Above all D) Except for
15. The early pioneers had to ____ many hardships to settle on the new land.
A) go into B) go through C) go back on D) go about
16. We should keep a ____ eye on the prisoners every moment.
A) jealous B) envious C) jealousy D) envy
17. I would appreciate ____ it a secret.
A) your keeping B) you to keep
C) that you keep D) that you will keep
18. Over the last fifteen years, running has become a popular ____ for 30 million participants of the ages.
A) fantasy B) pastime C) symposium D) penalty
19. Now the cheers and applause ____ in a single sustained roar.
A) mingled B) concentrated C) assembled D) permeated
20. I couldn’t find ____ , and so I took this one.
A) a large enough coat B) an enough large coat
C) a large coat enough D) a coat enough large
21. ____ quite recently, most mothers in Britain did not take paid work outside the home.
A) Before B) Until C) From D) Since
22. Tryon was extremely angry, but cool-headed enough to ____ storming into the boss’s office.
A) prevent B) prohibit C) turn D) avoid
23. They are sure they have all the facts they need to ____ the existence of a black hole.
A) obtain B) maintain C) verify D) display
24. The town planning commission said that their financial outlook for the next year was optimistic. They expect increased tax ____.
A) efficiency B) revenues C) privileges D) validity
25. It is not ---_______ for me to return all the books to the library now because I still need some of them for my research.
A) continuous B) difficult C) convenient D) sufficient
26. He is the only person who can ____ in this case, because the other witnesses were killed mysteriously.
A) testify B) charge C) accuse D) rectify
27. This boy was _______ for what he had done in the class.
A) scolded B) overcome C) inclined D) displayed
28. On weekend my grandpa usually ____ a glass of wine.
A) subscribes B) engages in C) hangs on D) indulges in
29. The leader of the expedition ____ everyone to follow his example.
A) promoted B) reinforced C)sparked D) inspired
30. We must look beyond ____ and assumptions and try to discover what is missing.
A) justifications B) illusions C) manifestations D) specifications
31. The government is trying to do something to ____ better understanding between the two nations .
A) raise B) promote C) heighten D) increase
32. The soldier was _____ of running away when the enemy attacked.
A) scolded B) charged C) accused D) punished
33. People appreciate ____ with him because he has a good sense of humor.
A) to work B) to have worked C) working D) having worked
34. When a spacecraft travels, one of the major problems is reentry into the Earth’s _______.
A) surface B) atmosphere C) attitude D) bent
35. We are _______ at the rapid progress Mark has made in this semester.
A) distinguished B) annoyed C) astonished D) scored
36. He tried to _______relations with his former wife but he failed.
A) measure B) maintain C) shelter D) reply
37. It can be said without any ____ that this factory can products 100,000 bikes every month.
A) boast B) exaggerate C) boastful D) exaggeration
38. An employee told the government official that “US” is short ____ “Uncle Sam”.
A) for B) to C) with D) on
39. The committee did not ____ of the plan to build a new bridge over the river, for it will cost too much.
A) prove B) approve C) disapprove D) disprove
40. A few villagers were ____ of “Lord Williams” but most saw nothing that aroused doubts until later.
A) suspicious B) suspicion C) doubtable D) doubted
41. Women do not usually eat the recommended daily ____ of iron.
A) section B) allowance C) share D) part
42. He wasn’t ___ to sit and watch, but he could not stand unaided on the soft sand because of his lameness.
A) conceited B) content C) concept D) concentrated
43. We ____ Edison’s success to his intelligence and hard work.
A) subject B) attribute C) owe D)refer
44. The police accused him of setting fire to the building but he denied ____ in the area on the might of the fire.
A) to be B) to have been C) having been D) be
45. She accused the man _____ breaking into her house.
A) at B) of C) for D) with
46. Many people like white color as it is a ____ of purity.
A) symbol B) sign C) signal D) symptom
47. Everyone should be ____ to a decent standard of living and an opportunity to be educated.
A) attributed B) entitled C) identified D) justified
48. You have nothing to ____ by refusing to listen to our advice.
A) gain B) grasp C)seize D) earn
49. On weekend my grandpa usually ____ a glass of wine.
A) subscribes B) engages in C) hangs on D) indulges in
50. Though ____ in a big city, Peter always prefers to paint the primitive scenes of country life.
A) grown B) raised C) tended D) cultivated
51. The manager urged his staff not to ____ the splendid opportunity.
A) drop B) miss C) escape D) slide
52. Mr. Smith was the only witness who said that the fire was ____.
A) mature B) deliberate C) meaningful D) innocent
53. This is the nurse who ____ to me when I was ill in hospital.
A) accompanied B) attended C) entertained D) shielded
54. Although he had looked through all the reference material on the subject, he still found it hard to understand this point and her explanation only ____ to his confusion.
A) extended B) amounted C) added D) turned
55. This morning in the class, our teacher lost his _______ at last because he could not stand any more.
A) temper B) terror C) verse D) contain
56. He keeps on with physical training in winter ___________cold it is .
A) whatever B) no matter how C) whether or not D) although
57. The woman was worried about the side effects of taking aspirins, but her doctor____ her that it is absolutely harmless.
A) retrieved B) released C) reassured D) revived
58. We should make a clear ____ between the two scientific terms for the purpose of our discussion.
A) separation B) discrimination C) deviation D) distinction
59. Most broadcasters maintain that TV has been unfairly criticized and argue that the power of the medium is ____.
A) granted B) implied C) exaggerated D) remedied
60. His wife is constantly finding ____ with him, which makes him very angry.
A) errors B) shortcomings C) fault D) flaw
61. We must look beyond ____ and assumptions and try to discover what is missing.
A) justifications B) illusions C) manifestations D) specifications
62. Most broadcasters maintain that TV has been unfairly criticized and argue that the power of the medium is ____.
A) granted B) implied C) exaggerated D) remedied
63. He is watching TV? He is _____ to be cleaning his room.
A) known B) supposed C) regarded D) considered
64. The Smiths decided to _____ a boy and a girl though they already had three children.
A) adapt B) bring C) receive D) adopt
65. I had just started back for the house to change my clothes ____ I heard voices.
A) as B) when C) after D) while
66. We can not trust him any more because he often ________ his duty.
A) owes B) spoils C) deserts D) neglects
67. In order to increase our output, we need to import more production _______.
A) facilities B) hens C) votes D) artists
68. Free medical service is _______ to nearly all the college students in China.
A) favorite B) available C) convenient D) average
69. Iron supplements may produce a feeling of wanting to ____ , and may be poisonous in some cases.
A) throw away B) throw up C) throw in D) throw out
70. Grant Wood instantly ____ to fame in 1930 with his painting American Gothic, an often-copied interpretation of the solemn pride of American farmers.
A) arise B) rise C) rose D) raised
71. I rub cream into the old woman’s yellow skin, feeling perfectly the ____ of each bone in the back.
A) outline B) organization C) structure D) frame
72. If you had been ____ in your study, you would have passed the examination without any difficulty.
A) big-minded B) single-minded C) broad-minded D)narrow-minded
73. My English professor told me to____ my vocabulary, to ____ my sentence length and to ____ my tone.
A) amplify; justify; enlarge B)enlarge; justify; diversify
C) diversify; enlarge; amplify D) enlarge; amplify; diversify
74. Women do not usually eat the recommended daily ____ of iron.
A) section B) allowance C) share D) part
75. The point in ____ by correspondence is not whether we should do it but whether we can do it.
A) argument B) debate C) dispute D) controversy
76. ____ their difference, the couple were developing an obvious and genuine affection for each other.
A) But for B) For all C) Above all D) Except for
77. We ____ Edison’s success to his intelligence and hard work.
A) subject B) attribute C) owe D)refer
78. We should keep a ____ eye on the prisoners every moment.
A) jealous B) envious C) jealousy D) envy
79. Under the present system, state enterprises must ____ all profits to the government.
A) turn down B) turn up C) turn out D) turn in
80. Many people like white color as it is a ____ of purity.
A) symbol B) sign C) signal D) symptom
81. Now the cheers and applause ____ in a single sustained roar.
A) mingled B) concentrated C) assembled D) permeated
82. John Dewey believed that education should be a preparation for life that a person learns by doing, and that teaching must ____ the curiosity and creativity of children.
A) seek B) stimulate C) shape D) secure
83. He asked us to ____ them in carrying through their plan.
A) provide B) arouse C) assist D) persist
84. Mr. Smith was the only witness who said that the fire was ____.
A) mature B) deliberate C) meaningful D) innocent
85. Tryon was extremely angry, but cool-headed enough to ____ storming into the boss’s office.
A) prevent B) prohibit C) turn D) avoid
86. She gave him back the money she’d stolen, for ____ sake.
A) consent’s B) conscience’s C) her D) conscious
87. If you have any problems during your study here, please do not _______ to call me for help
A) hesitate B) despair C) urge D) request
88. Some lazy men would rather _______ than work.
A) indicate B) declare C) solve D) starve
89. He keeps on with physical training in winter ___________cold it is .
A) whatever B) no matter how C) whether or not D) although
90. The designer has applied for a ____ for his new invention.
A) tariff B) discount C) version D) patent
91. The soldier was _____ of running away when the enemy attacked.
A) scolded B) charged C) accused D) punished
92. Had he worked hard, he _____ the exams.
A) must have got through B) would have got through
C) would get through D) could get through
93. The pressure _____ causes Americans to be energetic, but it also puts them under a constant emotional strains.
A) to compete B) competing C) to be competed D) having competed
94. He tried to _______relations with his former wife but he failed.
A) measure B) maintain C) shelter D) reply
95. He _______ to study harder in the future so that he could have more opportunities to find a better job.
A) resolved B) resorted C) requested D) reserved
96. The engineers in this lab spent several weeks _______ their plans for the new bicycle.
A) counting B) stripping C) elaborating D) casting
97. James Montgomery is famous for his army ____ posters of World Wars I and II.
A) recruited B) recruiting C) recruit D) recrutation
98. James Fraser ____ tradition by using three actual American Indians as models for his creation.
A) went out B) went for C) went in D) went against
99. His parents did not approve of his plan to go and study abroad with a girl they had never met, but he ____ and married her.
A) went against B) went for C) went for nothing D) went ahead
100. The ____ of Liberty was dedicated on an island in Upper New York Bay in 1886.
A) Status B) Statue C) Stature D) State
101. After the war, a character called Uncle Sam began appearing in political cartoon, his from ____ from an earlier cartoon character called Brother Jonathan.
A) involving B) changing C) evolving D) altering
102. Her skin was dry after ____ to the wind during the trip.
A) failure B) disclosure C) exposure D) pressure
103. She accused the man _____ breaking into her house.
A) at B) of C) for D) with
104. When Mr. Jones gets old, he will ____ his business to his son.
A) take over B) hand over C) think over D) get over
105. My camera can be ____ to take pictures in cloudy or sunny conditions.
A) treated B) adjusted C) adopted D) remedied
106. Those acting for the defendant proposed to appeal ____ the sentence.
A) to B)against C) for D) out
107. The manager promised to keep me ____ of how our business was going on.
A) to be informed B) on informing C) informed D) informing
108. Our hopes ___ and fell in the same instant.
A) aroused B) arose C) raised D) rose
109. I’m very sorry to have ____ you with so many questions on such an occasion.
A) interfered B) offended C) impressed D) bothered
110. Though ____ in a big city, Peter always prefers to paint the primitive scenes of country life.
A) grown B) raised C) tended D) cultivated
111. In the Chinese household, grandparents and other relative play ___ roles in raising children.
A) incapable B) indispensable C) insensible D) infinite
112. Although he had looked through all the reference material on the subject, he still found it hard to understand this point and her explanation only ____ to his confusion.
A) extended B) amounted C) added D) turned
113. He was such a ____ speaker that he held our attention every minute of the three-hour lecture.
A) specific B) dynamic C) heroic D) diplomatic
114. This is the nurse who ____ to me when I was ill in hospital.
A) accompanied B) attended C) entertained D) shielded
115. The computer has brought about surprising technological changes ____ we organize and produce information.
A) in a way B) in the way C) in that way D) in no way
116. As a teacher, you should not _______ the students from asking questions in class.
A) ruin B) restrain C) import D) impose
117. Students with _______ problems may apply for student loans.
A) economic B) financial C) male D) economical
118. We should make a clear ____ between the two scientific terms for the purpose of our discussion.
A) separation B) discrimination C) deviation D) distinction
119. Radio, television and press ____ of conveying news as information.
A) are the most common three means
B) are the most three common means
C) are the three most common means
D) are three the most common means
120. Many manufacturers were accused of concentrating too heavily on cost reduction, often at the ____ of the quality of their products.
A) expense B) exposure C) expansion D) expectation
121. _____ their differences , the couple were developing an obvious and genuine affection for each other .
A) But for B) For all C) Above all D) Except for
122. Since the matter was extremely _____, we dealt with it immediately.
A) tough B) tense C) urgent D) instant
123. The medicine is on sale everywhere. You can get it at ______ chemist’s.
A) each B) some C) certain D) any
124. With the help of the government , a large number of people ---_______ after the flood in 1991.
A) survived B) suspended C) suffered D) suspected
125. He always has a lot of _______ ideas in his mind , and sometimes we do not even know what he is thinking about.
A) novel B) spoil C) acceptable D) additional
126. John _______ to be a polite man. But in fact he is very rude.
A) pretends B) assures C) affords D) melts
127. A study suggests that even ____ exercise may lead to reduced iron in the blood of women.
A) modern B) moderate C) excess D) excessive
128. Because women often ____ their diet to control weight, they may not consume enough iron-rich food, and are liable to experience a deficiency.
A) restrict B) strict C) stuck D) construct
129. They ____ that the aging population is adding 1 per cent yearly to health service costs.
A) add B) calculate C) add to D) calculate on
130. A ____ is a person who ____ _____.
A) crime; commit; criminal B) commit; criminal; crimes
C) commit; crimes; criminal D) criminal; commits; crimes
131. Earthquake survival supplies include a torch, a spade, some rope and a radio ____.
A) conceiver B) receiver C) perceiver D) deceiver
132. The short story ____ the heart of the little boy with its unusual plot.
A) captured B) cost C) cast D) chased
133. If we say some food is ____, we mean it is safe to eat.
A) ideal B) editable C) ideate D) edible
134. Most people came to realize that it was about time the government ____ further measures to control the population.
A) must take B) is taking C) takes D) took
135. I always ____ what I have said.
A) get to B) hold to C) lead to D) see to
136. There were some ____ flowers on the table.
A) artificial B) unnatural C) false D) unreal
137. Which sport has the most expenses ____ training equipment, players’ personal equipment and uniforms?
A) in place of B) in terms of C) by means of D) by way of
138. In Africa, educational costs are very low for those who are ____ enough to get into universities.
A) ambitious B) fortunate C) aggressive D) substantial
139. If a person talks about his weak points, his listener is expected to say something in the way of ____.
A) persuasion B) remedy C) encourage D) compromise
140. Areas where students have particular difficulty have been treated ____ particular care.
A) by B) in C) under D) with
141. Operations which left patients ____ in need of long periods recovery time now leave them feeling relaxed and comfortable.
A) exhausted B) abandoned C) injured D) deserted
142. Everyone should keep a sense of responsibility ____ what he has done.
A) of B) for C) with D) to
143. I didn’t ____ to take a taxi but I had to as I was late.
A) mean B) assume C) hope D) suppose
144. The French pianist who had been praised very highly ____ to be a great disappointment.
A) turned up B) turned in C) turned out D) turned down
145. I have not heard anything from him since his _______.
A) departure B) fault C) foundation D) acceptance
146. Keep in __________ that all people are different and some may progress faster than others.
A) head B) brain C) heart D) mind
147. Sometimes it is very difficult to _______ some of the English words. Even the native speaker can not help.
A) decrease B) create C) define D) delight
148. If a person talks about his weak points, his listener is expected to say something in the way of ____.
A) persuasion B) remedy C) encourage D) compromise
149. Within two weeks of arrival, all foreigners had to ____ with the local police.
A) inquire B) register C) consult D) resolve
150. His intelligence and experience will enable him to ____ the complicated situation.
A) cope with B) settle down C) intervene in D) interfere with
二、阅读理解
1．
I left my friend’s house shortly after seven. It was still too early for me to have my evening meal, so I walked along the seafront (滨海马路) for about an hour until I began to feel hungry. By that time I was not far from a favorite restaurant of mine, where I often went to eat two or three times a week. I knew the owner well and frequently complimented (赞美, 恭维) him on his excellent cooking.
I went into the restaurant, which was already crowded, and ordered my meal. While I was waiting for the soup to arrive, I looked around to see if I knew anyone in the restaurant. It was then that I noticed that a man sitting at a corner table near the door kept glancing in my direction, as if he knew me, I certainly did not know him, for I never forgot a face. The man had a newspaper open in front of him, which he was pretending to read, though all the while I could see that he was keeping an eye on me. When the waiter brought my soup, the man was clearly puzzled by the familiar way in which the waiter and I addressed each other. He became even more puzzled as time went on and it grew more and more obvious that I was well known in the restaurant. Eventually he got up and went into the kitchen. After a few minutes he came out again, paid his bill and left without another glance in my direction.
When I had finished and was about to pay my bill, I called the owner of the restaurant over and asked him what the man had wanted. The owner was a little embarrassed by my question and at first did not want to tell me. I insisted. “Well,” he said, “that man was a detective.” “Really?” I said, considerably surprised. “He followed you here because he thought you were a man he was looking for,” the owner of the restaurant said. “When he came into the kitchen, he showed me a photograph of the wanted man. He certainly looked like you! Of course, since we know you here, I was able to convince him that he had made a mistake.” “It’s lucky I came to a restaurant where I am known,” I said, “otherwise I might have been arrested!”
1.When the author got to his favorite restaurant, it was ___________ .
A) already nine o’clock
B) eight o’clock on the dot
C) about two minutes past eight
D) slightly later than eight o’clock
2.The man sitting at the corner table near the door kept glancing in the direction of the author because he was __________________ .
A) interested in the personality of the author
B) making a study of the author
C) looking up and down the author
D) keeping a lookout over the author
3.The author was followed by the detective probably because he ___________ .
A) took after a suspect
B) was similar to a criminal in personality
C) was an accomplice
D) looked like a murderer
4.The detective had a newspaper open in front of him in order to ____________ .
A) read it in detail
B) cover up what he was really doing there
C) have it rechecked
D) wait for his food
5.According to the text, if the author had been a stranger in the restaurant, he would have been ____________________.
A) taken to court
B) followed
C) captured
D) sentenced to a few years’ imprisonment
2．
A very important world problem is the rapidly increasing pressure of population on land and on land resources.
It is not so much the actual population of the world but its rate of increase which is important. It works out to be about 1.6 per cent per annum net increase. In terms of numbers this means something like forty to fifty-five million additional people every year. Canada has a population of twenty million--rather less than six months' climb in world population. Take Australia. There are ten million people in Australia. So, it takes the world less than three months to add to itself a population which peoples that vast country. Let us take our own crowded country--England and Wales: forty-five to fifty million people--just about a year's supply.
By this time tomorrow, and every day, there will be added to the earth about 120,000 extra people, just about the population of the city of York.
This enormous increase of population will create immense problems. By A.D. 2000, unless something desperate happens, there will be as many as 7,000,000,000 people on the surface of this earth! So this is a problem which you are going to see in your lifetime.
Why is this enormous increase in population taking place? It is really due to the spread of the knowledge and the practice of what is coming to be called Death Control. Death Control is something rather different from Birth Control. Death Control recognizes the work of the doctors and the nurses and the hospitals and the health services in keeping alive people who, a few years ago, would have died of some of the incredibly serious killing diseases, as they used to be. Squalid conditions, which we can remedy by an improved standard of living, caused a lot of disease and dirt. Medical examinations at school catch diseases early and ensure healthier school children. Scientists are at work stamping our malaria and other more deadly diseases. If you are seriously ill there is an ambulance to take you to a modern hospital. Medical care helps to keep people alive longer. We used to think seventy was a good age; now eighty, ninety, it may be, are coming to be recognized as a normal age for human beings. People are living longer because of this Death Control, and fewer children are dying, so the population of the world is shooting up.
Imagine the position if you and I and everyone else living on earth shared the surface between us. How much should we have each? It would be just over twelve acres--the sort of size of a small holding. But not all that is useful land which is going to produce food. We can cut out one-fifth of it, for example, as being too cold. That is land which is covered with ice and snow--Antarctica and Greenland and the great frozen areas of northern Canada. Then we can cut out another fifth as being too dry--the great deserts of the world like the Sahara and the heart of Australia and other areas where there is no known water supply to feed crops and so to produce food. Then we can cut out another fifth as being too mountainous or with too great an elevation above sea level. Then we can cut out another tenth as land which has insufficient soil, probably just rock at the surface. Now, out of the twelve acres only about four are left as suitable for producing food.. But not all that is used. It includes land with enough soil and enough rainfall or water, and enough heat which, at present, we are not using, such as, for example, the great Amazon forests and the Congo forest and the grasslands of Africa. How much are we actually using? Only a little over one acre is what is required to support one human being on an average at the present time.
6. The world's population is increasing because _______.
A) the number of babies born every year is about 16 percent of the
total population
B) the birth rate is about 1.6 percent higher than the death rate
C) the birth rate is going up by 1.6 percent per annum
D) the death rate is going down by about 1.6 percent every year
7. The author mentions the different populations of Canada, Australia,
and England and Wales in order to _______.
A) show how small these countries are
B) show how quickly those countries are populated
C) emphasize the low rate of increase of world population
D) emphasize the high rate of increase of world population
8. According to the passage which of the following is not the cause for
death?
A) Poor living condition. B) Fatal diseases like malaria.
C) Poor medical service. D) Less food to feed people.
9. By "Death Control" the author means _______.
A) a rather different kind of Birth Control
B) control of the world's population
C) the prevention or cure of diseases
D) the spread of knowledge in the world
10. From the passage we can conclude _______.
A) the problem of land is not very serious
B) the problem of land can be solved by removing Death Control
C) the problem of land should be solved by reducing the population
D) there is still potential to tap in the use of land
3．
One of the most daring deep-space missions NASA has ever launched is turning out to be one of the least publicized. The target is a large asteroid (小行星) named 1992KD, which orbits the sun millions of miles from Earth. But that destination is almost incidental to the performance of the spacecraft that will make the trip. Though it looks little different from countless other unmanned probes NASA has launched, the ship will be navigated by an electronic brain that has been likened to HAL, the independent-minded computer in the film 2001, and will move through space under power of a system that has long been the stuff of technological fantasies: an ion propulsion (离子推进) engine.
If all goes as planned, Deep Space 1, scheduled for launch later this month, will be the forerunner of a new’ generation of spacecraft. While flight planners hope the ship will make some interesting observations about the target asteroid, including its composition and the structure of its surface, DS1 ‘s primary assignment is to validate a host of new technologies NASA has always considered too risky to try on a mission that may attract a great deal of public attention. Says Mar Rayman of Jet Propulsion Laboratory, DS1’ s chief engineer, “We have an unproven propulsion system, powered by an unproven solar panel, commanded by an unproven navigation system.
What is most remarkable about the spacecraft is how it gets from place to place. After being launched by an ordinary rocket, DS1 will be pushed through space by an engine that works by firing electrons into atoms of xenon gas, stripping each of an electron and giving the atoms an electric charge-ionizing them. The ions are then accelerated through an electric field and emitted from the thrusters at 65,000 m. p. h. Despite that speed, the particles produce little thrust, comparable to the weight of a piece of paper.
11. What is special about NASA’s planned deep-space mission regarding its publicity?
A) It is targeted at a large asteroid.
B) It is much less reported by the media.
C) It is the same as other unmanned probes.
D) It isn’t certain whether it will be successful.
12. What is the primary, purpose of the DS1 mission?
A) Testing new technologies for future spacecraft.
B) Calculating risks for the benefit of other missions.
C) Studying the surface of a large asteroid.
D) Proving a new generation of spacecraft.
13. Once launched, whether the spacecraft will reach its destination is incidental to the performance of all the following EXCEPT ___________.
A) the self-navigation system B) the ion-powered engine
C) the solar cells D) the flight planners
14. How does the DS1 leave the earth’s orbit?
A) By its special propulsion engine.
B) By a conventional rocket engine.
C) By firing electrons into the atoms of xenon gas.
D) By accelerating through an electric field.
15. Which of the following is NOT true according to this article?
A) The author likens the DS1’s navigation system to an electronic brain.
B) The DS1 is the first of a new breed of spacecraft.
C) The DS1 chief engineer has nothing to lose in such a mission.
D) The DS1’s power system used to be the dream of scientists.
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发表于 2015-7-6 10:38:38
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