[考研类试卷]考研英语模拟试卷271及答案与解析.doc

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1、考研英语模拟试卷 271及答案与解析 一、 Section I Use of English Directions: Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C or D. (10 points) 1 Most plants can make their own food from sunlight, (1)_ some have discovered that stealing is an easier way to live, Thousands of p

2、lant 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 find out how (5)_ are (6)_, mycologist Marti

3、n 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 plants not only (9)_ at how they survive, says B

4、idartondo, 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 minerals. Most plants have (12)_ a symbioti

5、c 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 number of plants sharing the same fungal web,

6、it was perhaps (17)_ that a few cheaters dubbed epiparasites would 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“. （ A） but （ B） if （ C） because （ D） though （ A） for （ B） with （ C） to （ D） without （

7、 A） realm （ B） net （ C） relation （ D） web （ A） only （ B） almost （ C） virtually （ D） actually （ A） others （ B） the others （ C） other （ D） the other （ A） getting by （ B） getting on （ C） getting through （ D） getting over （ A） evidences （ B） pictures （ C） traces （ D） tracks （ A） popular （ B） common （ C）

8、 ordinary （ D） widespread （ A） shows （ B） denotes （ C） indicates （ D） hints （ A） business （ B） commercial （ C） trading （ D） exchanging （ A） green （ B） land （ C） wild （ D） grown （ A） created （ B） developed （ C） designed （ D） formulated （ A） large （ B） vast （ C） great （ D） big （ A） floor （ B） level （

9、C） ground （ D） layer （ A） in turn （ B） in fact （ C） in return （ D） in the end （ A） offer （ B） equip （ C） help （ D） provide （ A） essential （ B） important （ C） possible （ D） inevitable （ A） in time （ B） overtime （ C） at times （ D） behind time （ A） taking （ B） grasping （ C） sucking （ D） catching （ A） i

10、nstead of （ B） in spite of （ C） in place of （ D） by contrast of Part A Directions: Read the following four texts. Answer the questions below each text by choosing A, B, C or D. (40 points) 21 Addiction is such a harmful behavior, in fact, that evolution should have long ago weeded it out of the popu

11、lation: if its 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 use of imaging to understand addiction, “the use of drugs has been recorded since the beginnin

12、g of civilization. Humans in my view will always want to experiment with things to make them feel good“. Thats because drugs of abuse co-opt the very brain functions that allowed our distant ancestors to survive in a hostile world. Our minds are programmed to pay extra attention to what neurologists

13、 call salience that 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 species survive. Drugs of abuse capitalize on this ready-made programming. When exposed to dr

14、ugs, our memory systems, reward circuits, decision-making skills and conditioning kick in salience in overdrive to create an all consuming pattern of uncontrollable craving. “Some people have a genetic predisposition to addiction“, says Volkow. “But because it involves these basic brain functions, e

15、veryone 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 addictions. Sometimes there might be a behavior-specific root of the problem. Volkows resear

16、ch group, for example, has shown that pathologically obese people who are compulsive eaters exhibit hyperactivity in the areas of the brain that process food stimuli including the mouth, lips and tongue. For them, activating these regions is like opening the floodgates to the pleasure center. Almost

17、 anything deeply enjoyable can turn into an addiction, though. Of course, not everyone becomes an addict. Thats because we have other, more analytical regions that can evaluate consequences and override mere pleasure seeking. Brain imaging is showing exactly how that happens. Paulus, for example, lo

18、oked at drug addicts enrolled in a VA hospitals 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 tasks involving cognitive skills and less able to adjust to new rules quickly. This suggest

19、ed 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 the prefrontal cortex, where rational thought can override impulsive behavior. Its impossible

20、 to say if the drugs might have damaged these abilities in the relapsers an effect rather than a cause of the chemical abuse but the fact that the cognitive deficit existed in only some of the drug users suggests that there was something innate that was unique to them. To his surprise, Paulus found

21、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 brains reward system, powered largely by the neurotransmitter dopamine. Investigators are looking specifically at the family of d

22、opamine 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 drugs hold. 21 According to Dr. Nora Volkow, the use, of drugs （ A） is a very harmful behavior that evolut

23、ion failed to get rid of. （ B） makes it hard for people to drive safely under its influence. （ C） has to do with peoples desire to achieve pleasant feelings. （ D） is understandable behavior because it dates back long ago. 22 According to the text, anyone may be addicted to drugs if they （ A） are bor

24、n 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. 23 Compulsive eaters are typical example of （ A） pleasure turning into habits and finally addicti

25、on. （ B） obese people with brain hyperactivity. （ C） those who cant control their mouth, lips and tongue. （ D） those who might also be addicted to gambling. 24 Paulus could accurately predict the relapsers because （ A） the part of their brain controlling cognitive skills is less active. （ B） a four-

26、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. 25 We can infer from the passage that we may cure addiction by （ A） scanning Of brain as often as poss

27、ible. （ B） consciously practicing cognitive skills. （ C） going through intensive rehabilitation programs. （ D） making the neurotransmitter less sensitive. 26 Good looks, the video-games industry is discovering, will get you only so far. The graphics on a modern game may far outstrip the pixellated b

28、lobs 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 better their behavior must also be more sophisticated, say researchers working at the in

29、terface between gaming and artificial intelligence(AI). Todays 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 Institute of Technology. AI, he suggests, offers an “untapped frontie

30、r“ of new possibilities. “We are topping out on the graphics, so whats 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, he says. Those in the industry agree. The high-definition graphic

31、s possible on next-generation games consoles, such as Microsofts Xbox 360, are raising expectatious across the board, says Neff Young of Electronic Arts, the worlds biggest games publisher. “You have to have high-resolution models, which requires high-resolution animation“, he says“, so now I expect

32、 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) conference. The aim, says Dr. Laird, who will chair the event, is to Increas

33、e 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 there were any computers to run it on; he also proposed the Turing te

34、st, 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 perspective, says Dr. Mateas, while Al researchers were, in turn, clueles

35、s 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 barrel of a gun. The behavior of enemies used to be pre-scripted: wa

36、it 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 and hand-coded behavior, the AI monsters in an FPS can reason from fir

37、st 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 dynamically shift, depending on whats happening“, says Fiona Sperry of

38、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 universities, says Dr. Laird. Such tools provide flexible environments for expe

39、riments, 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 revealed, and only by wrestling with technology does it give you insig

40、ht into what new kinds of content are possible, “he says. 26 According to the passage, good video-games used to be judged in terms of （ A） how sophisticated the behaviors of the characters are. （ B） how good-looking the characters seem to be. （ C） how sophisticated the artificial intelligence is. （

41、D） how much authenticity is displayed in the characters. 27 The last sentence“ so now I expect high-resolution behavior“ in the second paragraph most probably means （ A） the gameplay should be improved in the future. （ B） the behavior of game-designers should be refined. （ C） the definition of chara

42、cters in games should be more accurate. （ D） the expectations of gameplayers will be raised across the board. 28 The main purpose of the AIIDE conference is to （ A） increase communication between the eastern and western spheres. （ B） garantee the traffic of the gameplayers and the innovation of idea

43、s. （ C） cooperate to make more money from the computer game industry. （ D） tap the commercial and academic use of A1 through further communication. 29 The example of FPS is used in the passage to （ A） show how software controls an enemy behavior in a shooter game. （ B） show bow advanced technology c

44、an 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. 30 What can be inferred from the passage? （ A） Commercial games can be easily adopted as research tools in col

45、leges. （ 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. 31 Halfway through “The Rebel Sell“, the authors pause to make

46、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 up in a nice dark comer of the barn. On

47、ly 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 well-meaning but, in their view, ultimat

48、ely 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 create new segments of the market, and thu

49、s 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 worlds funniest joke. Why range so widely? The authors beef is with a very small group: le