1、考研英语-试卷 271及答案解析(总分：142.00，做题时间：90 分钟)一、Use of English(总题数：2，分数：80.00)1.Section I Use of EnglishDirections: Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C or D.（分数：40.00）_Most plants can make their own food from sunlight, (1)_ some have discovered that stea
2、ling is an easier way to live, Thousands of plant species get by (2)_ photosynthesizing, and over 400 of these species seem to live by pilfering sugars from an underground (3)_ of fungi(真菌). But in (4)_ a handful of these plants has this modus operandi been traced to a relatively obscure fungus. To
3、find out how (5)_ are (6)_, mycologist Martin Bidartondo of the University of California at Berkeley and his team looked in their roots. What they found were (7)_ of a common type of fungus, so (8)_ that it is found in nearly 70 percent of all plants. The presence of this common fungus in these plan
4、ts not only (9)_ at how they survive, says Bidartondo, but also suggests that many ordinary plants might prosper from a little looting, too. Plants have (10)_ relations to get what they need to survive. Normal, (11)_ plants can make their own carbohydrates through photosynthesis, but they still need
5、 minerals. Most plants have (12)_ a symbiotic relationship with a (13)_ network of what are called mycorrhizal fungi, which lies beneath the forest (14)_. The fungi help green plants absorb minerals through their roots, and (15)_, the plants normally (16)_ the fungi with sugars, or carbon. With a nu
6、mber of plants sharing the same fungal web, it was perhaps (17)_ that a few cheatersdubbed epiparasiteswould evolve to beat the system. (18)_, these plants reversed the flow of carbon, (19)_ it into their roots from the fungi (20)_ releasing it as “payment“.（分数：40.00）A.butB.ifC.becauseD.thoughA.forB
7、.withC.toD.withoutA.realmB.netC.relationD.webA.onlyB.almostC.virtuallyD.actuallyA.othersB.the othersC.otherD.the otherA.getting byB.getting onC.getting throughD.getting overA.evidencesB.picturesC.tracesD.tracksA.popularB.commonC.ordinaryD.widespreadA.showsB.denotesC.indicatesD.hintsA.businessB.comme
8、rcialC.tradingD.exchangingA.greenB.landC.wildD.grownA.createdB.developedC.designedD.formulatedA.largeB.vastC.greatD.bigA.floorB.levelC.groundD.layerA.in turnB.in factC.in returnD.in the endA.offerB.equipC.helpD.provideA.essentialB.importantC.possibleD.inevitableA.in timeB.overtimeC.at timesD.behind
9、timeA.takingB.graspingC.suckingD.catchingA.instead ofB.in spite ofC.in place ofD.by contrast of二、Reading Comprehensio(总题数：10，分数：58.00)2.Section II Reading Comprehension_3.Part ADirections: Read the following four texts. Answer the questions below each text by choosing A, B, C or D._Addiction is such
10、 a harmful behavior, in fact, that evolution should have long ago weeded it out of the population: if it“s hard to drive safely under the influence, imagine trying to run from a saber-toothed tiger or catch a squirrel for lunch, And yet, says Dr. Nora Volkow, director of NIDA and a pioneer in the us
11、e of imaging to understand addiction, “the use of drugs has been recorded since the beginning of civilization. Humans in my view will always want to experiment with things to make them feel good“. That“s because drugs of abuse co-opt the very brain functions that allowed our distant ancestors to sur
12、vive in a hostile world. Our minds are programmed to pay extra attention to what neurologists call saliencethat is, special relevance. Threats, for example, are highly salient, which is why we instinctively try to get away from them. But so are food and sex because they help the individual and the s
13、pecies survive. Drugs of abuse capitalize on this ready-made programming. When exposed to drugs, our memory systems, reward circuits, decision-making skills and conditioning kick insalience in overdriveto create an all consuming pattern of uncontrollable craving. “Some people have a genetic predispo
14、sition to addiction“, says Volkow. “But because it involves these basic brain functions, everyone will become an addict if sufficiently exposed to drugs or alcohol“. That can go for nonchemical addictions as well. Behaviors, from gambling to shopping to sex, may start out as habits but slide into ad
15、dictions. Sometimes there might be a behavior-specific root of the problem. Volkow“s research group, for example, has shown that pathologically obese people who are compulsive eaters exhibit hyperactivity in the areas of the brain that process food stimuliincluding the mouth, lips and tongue. For th
16、em, activating these regions is like opening the floodgates to the pleasure center. Almost anything deeply enjoyable can turn into an addiction, though. Of course, not everyone becomes an addict. That“s because we have other, more analytical regions that can evaluate consequences and override mere p
17、leasure seeking. Brain imaging is showing exactly how that happens. Paulus, for example, looked at drug addicts enrolled in a VA hospital“s intensive four-week rehabilitation program. Those who were more likely to relapse in the first year after completing the program were also less able to complete
18、 tasks involving cognitive skills and less able to adjust to new rules quickly. This suggested that those patients might also be less adept at using analytical areas of the brain while performing decision-making tasks. Sure enough, brain scans showed that there were reduced levels of activation in t
19、he prefrontal cortex, where rational thought can override impulsive behavior. It“s impossible to say if the drugs might have damaged these abilities in the relapsersan effect rather than a cause of the chemical abusebut the fact that the cognitive deficit existed in only some of the drug users sugge
20、sts that there was something innate that was unique to them. To his surprise, Paulus found that 80% to 90% of the time, he could accurately predict who would relapse within a year simply by examining the scans. Another area of focus for researchers involves the brain“s reward system, powered largely
21、 by the neurotransmitter dopamine. Investigators are looking specifically at the family of dopamine receptors that populate nerve cells and bind to the compound. The hope is that if you can reduce the effect of the brain chemical that carries the pleasurable signal, you can loosen the drug“s hold.（分
22、数：10.00）(1).According to Dr. Nora Volkow, the use, of drugs（分数：2.00）A.is a very harmful behavior that evolution failed to get rid of.B.makes it hard for people to drive safely under its influence.C.has to do with people“s desire to achieve pleasant feelings.D.is understandable behavior because it da
23、tes back long ago.(2).According to the text, anyone may be addicted to drugs if they（分数：2.00）A.are born with a predisposition to addiction.B.use certain chemicals long and frequently enough.C.have sufficient drugs or alcohol to use.D.create an all consuming pattern of uncontrollable craving.(3).Comp
24、ulsive eaters are typical example of（分数：2.00）A.pleasure turning into habits and finally addiction.B.obese people with brain hyperactivity.C.those who can“t control their mouth, lips and tongue.D.those who might also be addicted to gambling.(4).Paulus could accurately predict the relapsers because（分数
25、：2.00）A.the part of their brain controlling cognitive skills is less active.B.a four-week intensive rehabilitation program is not effective enough.C.he has the devices sophisticated enough to scan any brain damage.D.something innate to their brains prompt them to use drugs.(5).We can infer from the
26、passage that we may cure addiction by（分数：2.00）A.scanning Of brain as often as possible.B.consciously practicing cognitive skills.C.going through intensive rehabilitation programs.D.making the neurotransmitter less sensitive.Good looks, the video-games industry is discovering, will get you only so fa
27、r. The graphics on a modern game may far outstrip the pixellated blobs of the 1980s, but there is more to a good game than eye candy. Photo-realistic graphics make the lack of authenticity of other aspects of gameplay more apparent. It is not enough for game characters to look bettertheir behavior m
28、ust also be more sophisticated, say researchers working at the interface between gaming and artificial intelligence(AI). Today“s games may look better, but the gameplay is “basically the same“ as it was a few years ago, says Michael Mateas, the founder of the Experimental Game Lab at the Georgia Ins
29、titute of Technology. AI, he suggests, offers an “untapped frontier“ of new possibilities. “We are topping out on the graphics, so what“s going to be the next thing that improves gameplay?“ asks John Laird, director of the A1 lab at the University of Michigan. Improved Al is a big part of the answer
30、, he says. Those in the industry agree. The high-definition graphics possible on next-generation games consoles, such as Microsoft“s Xbox 360, are raising expectatious across the board, says Neff Young of Electronic Arts, the world“s biggest games publisher. “You have to have high-resolution models,
31、 which requires high-resolution animation“, he says“, so now I expect high-resolution behavior“. Representatives from industry and academia will converge in Marina del Rey, California, later this month for the second annual Artificial Intelligence and Interactive Digital Entertainment(AIIDE) confere
32、nce. The aim, says Dr. Laird, who will chair the event, is to Increase the traffic of people and ideas between the two spheres. “Games have been very important to AI through the years“, he notes. Alan Turing, one of the pioneers of computing in the 1940s, wrote a simple chess-playing program before
33、there were any computers to run it on; he also proposed the Turing test, a question-and-answer game that is a yardstick for machine intelligence. Even so, AI research and video games existed in separate worlds until recently. The Al techniques used in games were very simplistic from an academic pers
34、pective, says Dr. Mateas, while Al researchers were, in turn, clueless about modern games. But, he says, “both sides are learning, and are now much closer“. Consider, for example, the software that controls an enemy in a first-person shooter (FPS)a game in which the player views the world along the
35、barrel of a gun. The behavior of enemies used to be pre-scripted: wait until the player is nearby, pop up from behind a box, fire weapon, and then roll and hide behind another box, for example. But some games now use far more advanced“ planning systems“ imported from academia. “Instead of scripts an
36、d hand-coded behavior, the AI monsters in an FPS can reason from first principles“, says Dr. Mateas. They can, for example, work out whether the player can see them or not, seek out cover when injured, and so on. “Rather than just moving between predefined spots, the characters in a war game can dyn
37、amically shift, depending on what“s happening“, says Fiona Sperry of Electronic Arts. If the industry is borrowing ideas from academia, the opposite is also true. Commercial games such as “Unreal Tournament“, which can be easily modified or scripted, are being adopted as research tools in universiti
38、es, says Dr. Laird. Such tools provide flexible environments for experiments, and also mean that students end up with transferable skills. But the greatest potential lies in combining research with game development, argues Dr. Mateas. “Only by wrestling with real content are the technical problems r
39、evealed, and only by wrestling with technology does it give you insight into what new kinds of content are possible, “he says.（分数：10.00）(1).According to the passage, good video-games used to be judged in terms of（分数：2.00）A.how sophisticated the behaviors of the characters are.B.how good-looking the
40、characters seem to be.C.how sophisticated the artificial intelligence is.D.how much authenticity is displayed in the characters.(2).The last sentence“ so now I expect high-resolution behavior“ in the second paragraph most probably means（分数：2.00）A.the gameplay should be improved in the future.B.the b
41、ehavior of game-designers should be refined.C.the definition of characters in games should be more accurate.D.the expectations of gameplayers will be raised across the board.(3).The main purpose of the AIIDE conference is to（分数：2.00）A.increase communication between the eastern and western spheres.B.
42、garantee the traffic of the gameplayers and the innovation of ideas.C.cooperate to make more money from the computer game industry.D.tap the commercial and academic use of A1 through further communication.(4).The example of FPS is used in the passage to（分数：2.00）A.show how software controls an enemy
43、behavior in a shooter game.B.show bow advanced technology can help improve the quality of games.C.stress the importance of first principles in designing excellent games.D.point out that the characters in a war game should shift dynamically.(5).What can be inferred from the passage?（分数：2.00）A.Commerc
44、ial games can be easily adopted as research tools in colleges.B.College students can also benefit by playing high-resolution games.C.Further communication between the two circles may result in mutual benefit.D.Wresting with real content and technology will provide more solutions.Halfway through “The
45、 Rebel Sell“, the authors pause to make fun of “free-range“ chicken. Paying over the odds to ensure that dinner was not in a previous life, confined to tiny cages is all well and good. But “a free-range chicken is about as plausible as a sun-loving earthworm“: given a choice, chickens prefer to curl
46、 up in a nice dark comer of the barn. Only about 15% of “free-range“ chickens actually use the space available to them. This is just one case in which Joseph Heath, who teaches philosophy at the University of Toronto, and Andrew Potter, a journalist and researcher based in Montreal, find fault with
47、well-meaning but, in their view, ultimately naive consumers who hope to distance themselves from consumerism by buying their shoes from Mother Jones magazine instead of Nike. Mr. Heath and Mr. Potter argue that “the counterculture“, in all its attempts to be subversive, has done nothing more than cr
48、eate new segments of the market, and thus ends up feeding the very monster of consumerism and conformity it hopes to destroy. In the process, they cover Marx, Freud, the experiments on obedience of Stanley Milgram, the films“ Pleasantville“, “The Matrix“ and “American Beauty“, 15th-century table manners, Norman Mailer, the Unabomber, real-estate prices in central Toronto (more than once), the voluntary-simplicity movement and the world“s funniest joke. Why range so widely? The authors“ beef is with a very small group: left-wing activists
