1、2018年 6月大学英语六级真题试卷（二）及答案与解析 一、 Part I Writing 1 For this part, you are allowed 30 minutes to write an essay on the importance of building trust between businesses and consumers. You can cite examples to illustrate your views. You should write at least 150 words hut no more than 200 words. Section A
2、（ A） She advocates animal protection. （ B） She sells a special kind of coffee. （ C） She is going to start a cafe chain. （ D） She is the owner of a special cafe. （ A） They bear a lot of similarities. （ B） They are a profitable business sector. （ C） They cater to different customers. （ D） They help ta
3、ke care of customers pets. （ A） By giving them regular cleaning and injections. （ B） By selecting breeds that are tame and peaceful. （ C） By placing them at a safe distance from customers. （ D） By briefing customers on how to get along with them. （ A） They want to learn about rabbits. （ B） They like
4、 to bring in their children. （ C） They love the animals in her cafe. （ D） They give her cafe favorite reviews. （ A） It contains too many additives. （ B） It lacks the essential vitamins. （ C） It can cause obesity. （ D） It is mostly garbage. （ A） Its fancy design. （ B） TV commercials. （ C） Its taste a
5、nd texture. （ D） Peer influence. （ A） Investing heavily in the production of sweet foods. （ B） Marketing their products with ordinary ingredients. （ C） Trying to trick children into buying their products. （ D） Offering children more varieties to choose from. （ A） They hardly ate vegetables. （ B） The
6、y seldom had junk food. （ C） They favored chocolate-coated sweets. （ D） They liked the food advertised on TV. Section B （ A） Stretches of farmland. （ B） Typical Egyptian animal farms. （ C） Tombs of ancient rulers. （ D） Ruins left by devastating floods. （ A） It provides habitats for more primitive tr
7、ibes. （ B） It is hardly associated with great civilizations. （ C） It has not yet been fully explored and exploited. （ D） It gathers water from many tropical rain forests. （ A） It carries about one fifth of the world s fresh water. （ B） It has numerous human settlements along its banks. （ C） It is se
8、cond only to the Mississippi River in width. （ D） It is as long as the Nile and the Yangtze combined. （ A） Living a life in the fast lane leads to success. （ B） We are always in a rush to do various things. （ C） The search for tranquility has become a trend. （ D） All of us actually yearn for a slow
9、and calm life. （ A） She had trouble balancing family and work. （ B） She enjoyed the various social events. （ C） She was accustomed to tight schedules. （ D） She spent all her leisure time writing books. （ A） The possibility of ruining her family. （ B） Becoming aware of her declining health. （ C） The
10、fatigue from living a fast-paced life. （ D） Reading a book about slowing down. （ A） She started to follow the cultural norms. （ B） She came to enjoy doing everyday tasks. （ C） She learned to use more polite expressions. （ D） She stopped using to-do lists and calendars. Section C （ A） They will root
11、out native species altogether. （ B） They contribute to a regions biodiversity. （ C） They pose a threat to the local ecosystem. （ D） They will crossbreed with native species. （ A） Their classifications are meaningful. （ B） Their interactions are hard to define. （ C） Their definitions are changeable.
12、（ D） Their distinctions are artificial. （ A） Only a few of them cause problems to native species. （ B） They may turn out to benefit the local environment. （ C） Few of them can survive in their new habitats. （ D） Only 10 percent of them can be naturalized. （ A） Respect their traditional culture. （ B）
13、 Attend their business seminars. （ C） Research their specific demands. （ D） Adopt the right business strategies. （ A） Showing them your palm. （ B） Giving them gifts of great value. （ C） Drinking alcohol on certain days of a month. （ D） Clicking your fingers loudly in their presence. （ A） They are ve
14、ry easy to satisfy. （ B） They have a strong sense of worth. （ C） They tend to be friendly and enthusiastic. （ D） They have a break from 2:00 to 5 :30 p. m. （ A） He completely changed the company s culture. （ B） He collected paintings by world-famous artists. （ C） He took over the sales department of
15、 Readers Digest. （ D） He had the companys boardroom extensively renovated. （ A） It should be sold at a reasonable price. （ B） Its articles should be short and inspiring. （ C） It should be published in the world s leading languages. （ D） Its articles should entertain blue- and pink-collar workers. （
16、A） He knew how to make the magazine profitable. （ B） He served as a church minister for many years. （ C） He suffered many setbacks and misfortunes in his life. （ D） He treated the employees like members of his family. （ A） It carried many more advertisements. （ B） George Grune joined it as an ad sal
17、esman. （ C） Several hundred of its employees got fired. （ D） Its subscriptions increased considerably. Section A 26 Did Sarah Josepha Hale write “Mary s Little Lamb“ , the eternal nursery rhyme (儿歌 ) about a girl named Mary with a stubborn lamb? This is still disputed, but it s clear that the woman【
18、 C1】 _for writing it was one of America s most fascinating【 C2】 _. In honor of the poem s publication on May 24, 1830, here s more about the【 C3】 _author s life. Hale wasn t just a writer, she was also a【 C4】 _social advocate, and she was particularly【 C5】 _with an ideal New England, which she assoc
19、iated with abundant Thanksgiving meals that she claimed had “a deep moral influence“. She began a nationwide【 C6】 _to have a national holiday declared that would bring families together while celebrating the【 C7】 _festivals. In 1863, after 17 years of advocacy including letters to five presidents, H
20、ale got it. President Abraham Lincoln, during the Civil War, issued a【 C8】 _setting aside the last Thursday in November for the holiday. The true authorship of “Mary s Little Lamb“ is disputed. According to the New England Historical Society, Hale wrote only part of the poem, but claimed authorship.
21、 Regardless of the author, it seems that the poem was【 C9】 _by a real event. When young Mary Sawyer was followed to school by a lamb in 1816, it caused some problems. A bystander named John Roulstone wrote a poem about the event, then, at some point, Hale herself seems to have helped write it. Howev
22、er, if a 1916 piece by her great-niece is to be trusted, Hale claimed for the【 C10】 _of her life that “ some other people pretended that someone else wrote the poem“. A) campaign I) proclamation B) career J) rectified C) characters K) reputed D) features L) rest E) fierce M) supposed F) inspired N)
23、traditional G) latter O) versatile H) obsessed 27 【 C1】 28 【 C2】 29 【 C3】 30 【 C4】 31 【 C5】 32 【 C6】 33 【 C7】 34 【 C8】 35 【 C9】 36 【 C10】 Section B 36 Grow Plants Without Water A Ever since humanity began to farm our own food, we ve faced the unpredictable rain that is both friend and enemy. It come
24、s and goes without much warning, and a field of lush (茂盛的 ) leafy greens one year can dry up and blow away the next. Food security and fortunes depend on sufficient rain, and nowhere more so than in Africa, where 96% of farmland depends on rain instead of the irrigation common in more developed plac
25、es. It has consequences: South Africa s ongoing droughtthe worst in three decadeswill cost at least a quarter of its corn crop this year. B Biologist Jill Farrant of the University of Cape Town in South Africa says that nature has plenty of answers for people who want to grow crops in places with un
26、predictable rainfall. She is hard at work finding a way to take traits from rare wild plants that adapt to extreme dry weather and use them in food crops. As the earth s climate changes and rainfall becomes even less predictable in some places, those answers will grow even more valuable. “ The type
27、of farming I m aiming for is literally so that people can survive as it s going to get more and more dry,“ Farrant says. C Extreme conditions produce extremely tough plants. In the rusty red deserts of South Africa, steep-sided rocky hills called inselbergs rear up from the plains like the bones of
28、the earth. The hills are remnants of an earlier geological era, scraped bare of most soil and exposed to the elements. Yet on these and similar formations in deserts around the world, a few fierce plants have adapted to endure under ever-changing conditions. D Farrant calls them resurrection plants
29、(复苏植物 ). During months without water under a harsh sun, they wither, shrink and contract until they look like a pile of dead gray leaves. But rainfall can revive them in a matter of hours. Her time-lapse (间歇性拍摄的 ) videos of the revivals look like someone playing a tape of the plant s death in revers
30、e. E The big difference between “drought-tolerant“ plants and these tough plants: metabolism. Many different kinds of plants have developed tactics to weather dry spells. Some plants store reserves of water to see them through a drought; others send roots deep down to subsurface water supplies. But
31、once these plants use up their stored reserve or tap out the underground supply, they cease growing and start to die. They may be able to handle a drought of some length, and many people use the term “drought tolerant“ to describe such plants, but they never actually stop needing to consume water, s
32、o Farrant prefers to call them drought resistant. F Resurrection plants, defined as those capable of recovering from holding less than 0.1 grams of water per gram of dry mass, are different. They lack water-storing structures, and their existence on rock faces prevents them from tapping groundwater,
33、 so they have instead developed the ability to change their metabolism. When they detect an extended dry period, they divert their metabolisms, producing sugars and certain stress-associated proteins and other materials in their tissues. As the plant dries, these resources take on first the properti
34、es of honey, then rubber, and finally enter a glass-like state that is “the most stable state that the plant can maintain“ , Farrant says. That slows the plant s metabolism and protects its dried-out tissues. The plants also change shape, shrinking to minimize the surface area through which their re
35、maining water might evaporate. They can recover from months and years without water, depending on the species. G What else can do this dry-out-and-revive trick? Seedsalmost all of them. At the start of her career, Farrant studied “recalcitrant seeds (顽拗性种子 )“, such as avocados, coffee and lychee. Wh
36、ile tasty, such seeds are delicatethey cannot bud and grow if they dry out (as you may know if you ve ever tried to grow a tree from an avocado pit). In the seed world, that makes them rare, because most seeds from flowering plants are quite robust. Most seeds can wait out the dry, unwelcoming seaso
37、ns until conditions are right and they sprout (发芽 ). Yet once they start growing, such plants seem not to retain the ability to hit the pause button on metabolism in their stems or leaves. H After completing her Ph. D. on seeds, Farrant began investigating whether it might be possible to isolate the
38、 properties that make most seeds so resilient (迅速恢复活力的 ) and transfer them to other plant tissues. What Farrant and others have found over the past two decades is that there are many genes involved in resurrection plants response to dryness. Many of them are the same that regulate how seeds become d
39、ryness-tolerant while still attached to their parent plants. Now they are trying to figure out what molecular signaling processes activate those seed-building genes in resurrection plantsand how to reproduce them in crops. “ Most genes are regulated by a master set of genes,“ Farrant says. “ We re l
40、ooking at gene promoters and what would be their master switch. “ I Once Farrant and her colleagues feel they have a better sense of which switches to throw, they will have to find the best way to do so in useful crops. “Im trying three methods of breeding,“ Farrant says: conventional, genetic modif
41、ication and gene editing. She says she is aware that plenty of people do not want to eat genetically modified crops, but she is pushing ahead with every available tool until one works. Farmers and consumers alike can choose whether or not to use whichever version prevails: “Im giving people an optio
42、n. “ J Farrant and others in the resurrection business got together last year to discuss the best species of resurrection plant to use as a lab model. Just like medical researchers use rats to test ideas for human medical treatments, botanists use plants that are relatively easy to grow in a lab or
43、greenhouse setting to test their ideas for related species. The Queensland rock violet is one of the best studied resurrection plants so far, with a draft genome (基因图谱 ) published last year by a Chinese team. Also last year, Farrant and colleagues published a detailed molecular study of another cand
44、idate, Xerophyta viscosa, a tough-as-nail South African plant with lily-like flowers, and she says that a genome is on the way. One or both of these models will help researchers test their ideasso far mostly done in the labon test plots. K Understanding the basic science first is key. There are good
45、 reasons why crop plants do not use dryness defenses already. For instance, there s a high energy cost in switching from a regular metabolism to an almost-no-water metabolism. It will also be necessary to understand what sort of yield farmers might expect and to establish the plant s safety. “ The y
46、ield is never going to be high,“ Farrant says, so these plants will be targeted not at Iowa farmers trying to squeeze more cash out of high-yield fields, but subsistence farmers who need help to survive a drought like the present one in South Africa. “My vision is for the subsistence farmer,“ Farran
47、t says. “Im targeting crops that are of African value. “ 37 There are a couple of plants tough and adaptable enough to survive on bare rocky hills and in deserts. 38 Farrant is trying to isolate genes in resurrection plants and reproduce them in crops. 39 Farmers in South Africa are more at the merc
48、y of nature, especially inconsistent rainfall. 40 Resurrection crops are most likely to be the choice of subsistence farmers. 41 Even though many plants have developed various tactics to cope with dry weather, they cannot survive a prolonged drought. 42 Despite consumer resistance, researchers are p
49、ushing ahead with genetic modification of crops. 43 Most seeds can pull through dry spells and begin growing when conditions are ripe, but once this process starts, it cannot be held back. 44 Farrant is working hard to cultivate food crops that can survive extreme dryness by studying the traits of rare wild plants. 45 By adjusting their metabolism, resurrection plants can recover from an extended period of drought. 46 Resurrection plants can come ba
