1、大学英语六级改革适用（阅读）模拟试卷 122及答案与解析 Section A 0 Today nanotechnology(纳米技术 )is still in a formative phase. Yet it is maturing rapidly. Between 1997 and 2005, investment in nanotech research and development by governments around the world【 C1】 _from $ 432 million to about $4.1 billion, and corresponding indu
2、stry investment exceeded that of governments by 2005. By 2015 , products incorporating nanotech will contribute approximately $ 1 trillion to the global economy. Descriptions of nanotech typically characterize it purely in terms of the minute sizeassemblies between the size of an atom and about 100
3、molecular diameters(分子直径 ). That【 C2】 _makes it sound as though nanotech is merely looking to use infinitely smaller parts than conventional engineering. But rearranging the atoms and molecules leads to new【 C3】 _One sees a transition between the fixed behavior of individual atoms and molecules and
4、the adjustable behavior of collectives. Thus, nanotechnology might better be viewed as the【 C4】 _of quantum theory(量子论 )and other nano-specific phenomena to fundamentally control the properties and behavior of matter. The second stage, which began in 2005, focuses on active nanostructures that chang
5、e their size, shape, conductivity or other properties during use. New drug-delivery particles could release therapeutic(治疗的 )molecules in the body only after they reached their【 C5】 _diseased tissues. Electronic components such as transistors and amplifiers with adaptive functions could be reduced t
6、o single, complex molecules. Starting around 2010, workers will【 C6】 _expertise with systems of nanostructures, directing large numbers of intricate components to specified ends. One application could involve the guided self-assembly of nanoelectronic components into three-dimensional circuits and w
7、hole devices. Medicine could employ such systems to improve the tissue compatibility of implants, or perhaps even to build【 C7】_organs. After 2015-2020, the field will include molecular nanosystems. Whereas biological systems are water-based and markedly temperature-sensitive, these molecular nanosy
8、stems will be able to operate in a far wider range of environments and should be much faster. Computers and robots could be reduced to【 C8】 _small sizes. New interfaces linking people directly to electronics could change telecommunications. Over time, therefore, nanotechnology should benefit every i
9、ndustrial sector and health care field. Nanotech does, however, pose new challenges to risk governance as well. Internationally, more needs to be done to collect the scientific information needed to resolve the【 C9】 _and to install the proper regulatory oversight. Helping the public to【 C10】 _nanote
10、ch soberly in a big picture that retains human values and quality of life will also be essential for this powerful new discipline to live up to its astonishing potential. A)ingenious I)cultivate B)properties J)targeted G)ambiguities K)perceive D)soared L)depiction E)extraordinarily M)illuminate F)ar
11、tificial N)compulsory G)indignation O)application H)instantaneously 1 【 C1】 2 【 C2】 3 【 C3】 4 【 C4】 5 【 C5】 6 【 C6】 7 【 C7】 8 【 C8】 9 【 C9】 10 【 C10】 Section B 10 Rainforest City AA patch of tropical rainforest has twice the number of mammal species, five times the bats and birds and ten times the t
12、ypes of tree than an identical sized patch of temperate forest. Explaining this diversity is extremely difficult, but much of the answer lies in the unique complexity, productivity and dynamism of the place. These three features have simultaneously fed upon each other to erect and populate the equiv
13、alent of vast, buzzing metropolises in the living world. BIn fact, the more we look at the rainforest, the more we see parallels with a city. Just like a city, the rainforest has “guilds“ groups that share a common livelihood. Where the city may have guilds of locksmiths and fishmongers(鱼贩 ), the ra
14、inforest has guilds of understorey nectar eaters and emergent epiphytes(附生植物 ). And, just as a large city offers more employment opportunities than a small town, the rainforest has significantly more guilds than other habitats. This is partly due to its more complex structure the fact that there is
15、an understorey means species can find a livelihood in the understorey but the rainforest is also effectively open all year and so it offers employment that is simply not available in other habitats. CA deckchair attendant in Britain has to do odd jobs in the winter, but in Thailand its a year-round
16、occupation. Similarly, no animal can be just a seed-eater in an oak forest, because acorns only fall in autumn. In the rainforest, seeds are always falling from the canopy(树冠 ), and so seed-eating is a legitimate profession it has its own guild. Similarly, due to the year-round demand in cities,spec
17、ialists such as carpet-cleaners, copywriters and couriers can thrive, while in a small town, they are absent. DThe rainforest “ job market“ is also enormous as a result of its permanently booming “economy“. In nature, energy is the currency, and the incredible productivity of the rainforest ensures
18、that theres always enough of it around to enable millions of species to live side by side. And, to avoid competition, natural selection has made sure that, even within a guild there are tiny differences in the diets, habitats or behaviors of each member. The rainforest could therefore be regarded as
19、 a vast association of specialists, a community of animals and plants that ply their own very particular trade. In insects, the specialization is extreme. Most live on only one or two species of plant. One tree in Panama was found to have 163 species of beetles that were exclusive to that type of tr
20、ee. EMost rainforest plants protect their leaves with poisons. In order to eat a plants leaves, the insects have to evolve to become tolerant to its particular cocktail of toxins(毒素 ). After thousands of years, most herbivorous insects are committed to living on their host plant alone. So, every poi
21、son-laced rainforest tree has a whole community of species living on, under and around it that are not found anywhere else. This situation is not unique to the rainforest. The same happens in Britain. In oak or Scots pine forests, a host of species live on just the oak trees or Scots pines. But the
22、fact is that in these forests, virtually every tree is an oak or a Scots pine. FWhat makes the rainforest so special, and so diverse, is that in one hectare there can be 300 different types of tree, each with its own exclusive community. In one tract of forest there are thousands, and worldwide ther
23、e could be up to 50,000 canopy-tree species. To an insect, the rainforest isnt just one job market, but thousands of different job markets, all located in the same city. This “mosaic(组合 )of trees“ is probably the single most important cause of diversity in the rainforest, and yet we dont really unde
24、rstand how it happens that is, why you dont normally find groves of trees in the rainforest. GIt could be that the 50,000 different trees suit 50,000 different types of plot and that the best tree for the spot excludes all the others. Or, it could be that all the trees are as “good“ as each other an
25、d that the forest is trapped in an endless game of tick-tack-toe(三连游戏 )with no ultimate winner. Or, it could be that some species are better than the others and are in the process of taking over, but because this process would take centuries, they never quite manage it before something such as a sto
26、rm or landslide puts them back to square one. HBut none of these explanations answers a simple question: if this is true for the rainforest, why isnt it true for an oak forest in England? The only theory that solves this puzzle is one that looks back to animals for an answer. Remember the guild of s
27、eed-eaters? In the rainforest a long list of species belongs to this guild. There are beetles and weevils(象鼻虫 ), squirrels and mice, rats, birds and larger mammals such as forest pigs, deer and tapirs. When this gang finds a tree in fruit, they feast until virtually no seed survives. The only seeds
28、that are spared are those scattered far and wide, lying alone on the forest floor. It is these seeds that will go on to create the next generation of canopy trees one that, like the previous generation, is also scattered far and wide. IThis is how the seed-eaters might create a mosaic of trees by st
29、opping any one tree from becoming too common. It wouldnt happen in an English oak forest because there is no guild of seed-eaters its not a year-round occupation. No one doubts that the rainforest is extremely valuable, but not everyone sees this value in the same way. Timber merchants, for example,
30、 see one kind of value, and environmentalists see another. To many scientists, a rainforest is most valuable when left alone to prosper without human interference, but with a growing human population, a global market for extracted goods and the extent of poverty around the equator, an evaluation of
31、the rainforest has to be more practical than this. JA new breed of rainforest valuation attempts to fit into the accounting books of nations and international organisations. It speaks the language of accountants, costs both the benefits of an intact rainforest and the losses of a vanished one, works
32、 out a forests “ natural capital“ and assesses its contribution to “environmental services“. Its grand conclusion:each hectare of intact rainforest is worth about 4, 500. It may not sound much, but that puts more than 7. 5trillion in the pockets of some of the most troubled countries on Earth. KSo w
33、here does this figure come from? Three quarters of it represents the uncollected harvest of a living rainforest. Managed sensibly, a wild forest can yield all sorts of sustainable crops timber, fruit, nuts, fiber, pulpwood, gums, resins, oils, veneer and there are many more treasures in there that w
34、e havent discovered yet. At least 3,000 fruits are known from rainforest plant collections, but only 200 of these are now in the marketplace. There are thousands of timbers, resins and oils that weve never analyzed. LAnd, perhaps most important of all, the rainforest is a natural pharmacy(药房 ). All
35、those poisonous plants are a goldmine of possible drugs. To date, less than one percent of rainforest plants have been examined for medicinal uses, but even this tiny percentage yields a quarter of all prescription drugs. Estimates suggest that the market value of those still secreted in the forest
36、would run to hundreds of billions of pounds. MThe remaining quarter stems from the value of the chores that the rainforest carries out on our behalf purifying air and water, preventing floods and drought, pollinating(授粉 )our crops, controlling our pests. Fertilizing our soil and reducing the effects
37、 of global wanning by storing carbon. If the rainforest disappears. Well have to pick up the tab for all of these services, and this means that each time a hectare of forest is felled it actually costs us money. NWhen youve done the sums, the rainforest is actually worth more whole than in pieces. E
38、ach time another hectare is removed, humanity effectively takes a loss. Many of us already knew this, but now it has been written in a language that everyone can understand. 11 The next generation of rainforest trees is created by the seeds lying far and wide on the forest floor. 12 Because of more
39、“guilds“ in common, the rainforest is compared to a city. 13 The figures provided by the evaluation actually show that we should try to keep the rainforest as a whole. 14 The new way of calculating the monetary value of a rainforest assesses its worth in environmental services. 15 The insects live o
40、n poisonous rainforest trees by becoming immune to the poison. 16 The unique features of the tropical rainforest are complexity, dynamism and productivity. 17 According to many scientists, the prosperity of a rainforest is less important than its practical value. 18 Compared with the seed-eating in
41、a temperate forest, the one in the rainforest is a valid action. 19 In the rainforest, some superior trees are replacing others in an extremely slow process. 20 The unfound, uncollected and unexamined treasures account for three fourths of the rainforests total worth. Section C 20 To listen to some
42、school reformers, youd think there are no urban traditional public schools that are successful. Heres a different story, adapted and excerpted from Improbable Scholars; The Rebirth of a Great American School System and a Strategy for Americas Schools(Oxford University Press), by David Kirp, professo
43、r of public policy at the University of California at Berkeley. He is a former newspaper editor and policy consultant, as well as the author of numerous articles in various publications and several books. What would it really take to give students a first-rate education? Some argue that our schools
44、are irremediably broken and that charter schools offer the only solution. The striking achievement of Union City, N. J. bringing poor, mostly immigrant kids into the educational mainstream argues for reinventing the public schools we have. Union City makes an unlikely poster child for education refo
45、rm. Its a poor community with an unemployment rate 60 percent higher than the national average. Three-quarters of the students live in homes where only Spanish is spoken. A quarter are thought to be undocumented, living in fear of deportation. Public schools in such communities have often operated a
46、s factories for failure. This used to be true in Union City, where the schools were once so wretched that state officials almost seized control of them. How things have changed. From third grade through high school, students achievement scores now approximate the statewide average. Whats more, in 20
47、11, Union City boasted a high school graduation rate of 90 percent roughly 10 percentage points higher than the national average. Last year, 75 percent of Union City graduates enrolled in college, with top students winning scholarships to the Ivies. As someone who has worked on education policy for
48、four decades, Ive never seen the likes of this. After spending a year in Union City working on a book, I believe its transformation offers school districts nationwide a usable strategy. Theres no miracle cure, no secret sauce or Superman just a handful of game-changing strategies, from preschool to
49、high school, that would be familiar to any educator with a pulse. Its a tale of continuous improvement over many years think of it as “tortoise beats hare. “ And Union City doesnt own a patent on the formula. Across the country, from Long Beach, California to Montgomery County, Maryland, school districts big and small, well-funded and meagerly-funded, predominantly Latino and black and heterogeneous(混杂的 ), are boosting achievement scores and shrinking t
