单选题 The common cold is the world's most widespread illness, which is probably why there are more myths about it than any of the other plagues (瘟疫) that flesh is heir to. The most widespread fallacy (谬误，谬论) of all is that colds are caused by cold. They are not. They are caused by viruses passed on from person to person. You catch a cold by coming into contact, directly or indirectly, with someone who already has one. If cold causes colds, it would be reasonable to expect the Eskimos to suffer from them permanently. But they do not. And in isolated arctic regions explorers have reported being free from colds until coming into contact again with infected people from the outside world by way of packages and mail dropped from airplanes. During the First World War soldiers who spent long periods in the trenches, cold and wet, showed no 'increased' tendency to catch colds. In the Second World War prisoners at the notorious Auschwitz concentration camp, naked and starving, was astonished to find that they seldom had colds. At the Common Cold Research Unit in England, volunteers took part in experiment in which they submitted to the discomforts of being cold and wet for long stretches of time. After taking hot baths, they put on bathing suits, allowed themselves to be doused (浸泡) with cold water, and then stood about dripping wet in drafty rooms. Some wore wet socks all day while others exercised in the rain until close to exhaustion. Not one of the volunteers came down with a cold unless a cold virus was actually dropped in his nose. If, then, cold and wet have nothing to do with catching colds, why are they more prevalent in the winter? Despite the most painstaking research, no one has yet found the answer. One explanation offered by scientists is that people tend to stay together indoors more in cold weather than at other time, and this makes it easier for cold viruses to be passed on. No one has yet found a cure for the cold. There are drugs and pain suppressors such as aspirin, but all they do is relieve the symptoms.

单选题 名人效应(celebrity effect)是指因崇拜明星而进行模仿的心理现象。在我们生活中随处都能看到名人效应，比如我们会买所喜欢的明星代言的产品，做明星提倡的事情。名人效应既有优点，也存在不足。明星都是各自领域的精英，但在其他领域就不见得做得好。尤其是现如今一些年轻明星，他们的行为传达出的是堕落的信息，对年轻一代影响很不好。

单选题 Researchers for Cornell University and Intel produced a chip called Loihi that reportedly makes computers think like biological brains, according to Daily Mail. The researchers created the circuit on the chip, mirroring organic circuits found in the olfactory bulbs (嗅球) of a dog's brain, which is how they process their sense of smell. The Loihi chip can identify a specific odor on the first try and even tell other background smells, said Intel, according to Daily Mail. The chip can even detect smells humans emit when sick with a disease—which vary depending on the illness—and smells linked to environmental gases and drugs. The key to sniffer dogs isn't their olfactory system alone, but their incredible ability to remember—this is why they're trained. Similarly, the artificial intelligence of the chip is trained to identify different smells and remember them, so that next time, it knows. The chip processes information just like mammal brains by using electrical signals to process smells. When a person smells something, the air molecules interact with nasal receptors that forward signals to the olfactory bulb in the brain. Then the brain translates the signals to identify which smell it's experiencing, based on memories of previous experiences with the specific smell. 'We are developing a method for Loihi to mimic (模仿) what happens in your brain when you smell something,' said Senior Research Scientist in Intel's Lab, Nabil Imam, in a statement, according to Daily Mail. Imam added that the work 'demonstrates Loihi's potential to provide important sensing capabilities that could benefit various industries.' So far, the researchers have trained it on ten harmful smells. It can be installed on robots in airports to help identify hazardous objects, or integrated with sensors in power plants or hospitals to detect dangerous gases. Similar biotechnology has seen the implementation in grasshoppers recently outfitted with computer chips to sniff-out bombs. However, this negatively affects their lifespan, limiting their use. While sniffer dogs might one day be out of a job, the circuits using AI to mimic the process of smell bring us one step closer to recreating the human sensory system in artificial intelligence.

单选题Directions:Forthispart,youareallowed30minutestowriteashortessay.Youshouldwriteatleast120wordsbutnomorethan180words.Youshouldstartyouressaywithabriefdescriptionofthepictureandthenexpressyourviewsontheproblemoftrustcrisis.写作导航1.简要描述图片，指出人们之间缺少信任是一种不良社会现象，会产生严重后果；2.从政府、社会机构(媒体和学校)和个人三个层面出发阐述了解决办法；3.进行总结，建议人们从个人做起，谨小慎微，提高诚信意识。

单选题 We've Been Imagining Mountains All Wrong, Say Scientists A. From the simplest sketches to the most advanced scientific models, illustrations of mountains pretty much all look the same. Their classic pyramid form, wider at the bottom and narrowing all the way up to the top, has been ingrained in the human mind, and scientists have always assumed that the land area in mountain ranges decreases the higher you climb. Until now, that is. B. New research published Monday in Nature Climate Change reveals a surprising discovery that not only changes the way we think about mountains but could also have big implications for how we understand, monitor and protect the organisms that call them home. It turns out mountain ranges don't just come in the familiar pyramid form—in fact, most of them have a different shape entirely. C. Researchers Morgan Tingley and Paul Elsen used satellite data on mountain ranges from around the globe to analyze how the amount of the land area changed with increasing elevation (海拔). They learned that pyramidal mountain ranges account for just 32 percent of the mountain ranges on Earth. Of the remaining mountain ranges, six percent have an inverse, or upside-down, pyramid form, with the land area increasing toward the top; 23 percent have an hourglass (沙漏) shape, being wider and at the bottom and top and pinched (挤压) in the middle; and 39 percent have a diamond form, with less land areas at the top and bottom and more available in the middle. D. 'I did expect that we'd see some patterns that were not this classic pyramid,' says Elsen, lead author and PhD student in Princeton University's ecology and evolutionary biology department. In fact, Elsen got interested in conducting the study while doing field research in the Himalayas. He noticed that as he hiked to the tops of the mountains, the land area seemed to increase, rather than decrease, at high elevations. Still, he says, 'I had no idea that pyramid mountains would be the exception to the rule.' E. It's hard to tell the true form of a mountain range just by looking at any given mountain peak, since most individual mountains still come to a point at the very top. But mountain ranges are so big, and their topography (地形) so complex, that it would be impossible to observe their true shapes just by looking at them. That's why the researchers had to analyze satellite data, looking at the total surface area in relation to elevation across the whole mountain range, to complete their study. The way the land area is distributed on a landscape scale—whether the greatest area lies at the top, bottom or in the middle when you take into account all the slopes, ravines and plateaus that make up the mountains—is what determines a mountain range's designation as a pyramid, inverse pyramid, diamond or hourglass. F. The finding doesn't just flip our view of mountain topography. More importantly, it changes our understanding of how climate change can affect mountain-dwelling species, the authors say. Organisms that live on mountains are in a particular pickle when it comes to climate change. These species tend to be highly specialized and do best in particular habitats and narrow temperature ranges. As global temperatures rise, the best way to find cooler spots is to move higher up on the mountain. But in pyramidal mountain ranges, which get narrower toward the top, moving higher also means losing the land area. Having less available space can cause populations to shrink and can put them at an increased risk of dying out entirely. G. But Elsen and Tingley's research shows that the pyramid model doesn't hold true for all, or even most mountain ranges, meaning space shortages might not always fall where scientists think they do. In hourglass mountains, for example, the most constricted (狭窄的) space will be in the middle of the mountain, rather than at the top. On the other hand, species on diamond mountains will see the widest spaces in the middle. And species on inverse pyramids will enjoy increasing land areas all the way up to the top of the mountain. H. 'I think this is critical information that will really inform our understanding of mountain species,' says Robert Guralnick, a biodiversity scientist and curator (馆长) at the University of Florida's natural history museum, who was not involved with the study. 'The models we've been using are typically that mountain ranges are narrowing toward the top.' More realistic models and a better understanding of mountain topography can help conservationists make better decisions when monitoring and managing mountain species, the paper's authors say. 'This is absolutely an important study for informing our conservation policy,' Elsen says. Knowing where the land area is likely to be scarce can help conservationists target the right places and the right species. I. In some cases, new knowledge could even indicate that climate change doesn't threaten a species in quite the way scientists thought. The Himalayan monal, for example, is a colorful bird that lives in the Himalayan mountains, which have the hourglass form. Currently, the bird prefers an elevation that's right in the middle of the hourglass, says Morgan Tingley, senior author and assistant professor of ecology and evolutionary biology at the University of Connecticut. So space may be pinched for it now, but if warming temperatures force the bird into higher elevations, it will likely enjoy more space as it moves upward. J. On the other hand, a bright little bird called the beautiful nuthatch—which is already classified as a vulnerable species by the International Union for Conservation of Nature—lives just below the pinched part of the hourglass. If it were to flee to higher ground, it would lose the land area. 'This current research is showing that there are potentially optimistic futures for some species, and it's also highlighting these bottleneck zones,' Elsen says. K. The research is also relevant for species that move downslope in response to climate change, chasing the increased precipitation that comes with warmer temperatures. Before now, most scientists might have assumed that any species moving downhill would be able to take advantage of greater and greater land areas as it moved along. Now we know that in certain mountain ranges, these species may actually encounter a shortage in space as they move toward the base of the mountain, and their populations may shrink as a result.

单选题 How Your Language Affects Your Wealth and Health A. Does the language we speak determine how healthy and rich we will be? New research by Keith Chen of Yale Business School suggests so. The structure of languages affects our judgments and decisions about the future and this might have dramatic long-term consequences. B. There has been a lot of research into how we deal with the future. For example, the famous marshmallow (棉花糖) studies of Walter Mischel and colleagues showed that being able to resist temptation is predictive of future success. Four-year-old kids were given a marshmallow and were told that if they do not eat that marshmallow and wait for the experimenter to come back, they will get two marshmallows instead of one. Follow-up studies showed that the kids who were able to wait for the bigger future reward became more successful young adults. C. Resisting our impulses for immediate pleasure is often the only way to attain the outcomes that are important to us. We want to keep a slim figure but we also want that last slice of pizza. We want a comfortable retirement, but we also want to drive that dazzling car, go on that dream vacation, or get those gorgeous shoes. Some people are better at delaying gratification (满足) than others. Those people have a better chance of accumulating wealth and keeping a healthy life style. They are less likely to be impulse buyers or smokers, or to engage in unsafe sex. D. Chen's recent findings suggest that an unlikely factor, language, strongly affects our future-oriented behavior. Some languages strongly distinguish the present and the future. Other languages only weakly distinguish the present and the future. Chen's recent research suggests that people who speak languages that weakly distinguish the present and the future are better prepared for the future. They accumulate more wealth and they are better able to maintain their health. The way these people conceptualize the future is similar to the way they conceptualize the present. As a result, the future does not feel very distant and it is easier for them to act in accordance with their future interests. E. Different languages have different ways of talking about the future. Some languages, such as English, Korean, and Russian, require their speakers to refer to the future explicitly (明确地). Every time English-speakers talk about the future, they have to use future markers such as 'will' or 'going to.' In other languages, such as Mandarin, Japanese, and German, future markers are not obligatory (强制性的) . The future is often talked about similar to the way present is talked about and the meaning is understood from the context. A Mandarin speaker who is going to go to a seminar might say 'Wo qu ting jiangzuo,' which translates to 'I go listen seminar.' Languages such as English constantly remind their speakers that future events are distant. For speakers of languages such as Mandarin future feels closer. As a consequence, resisting immediate impulses and investing for the future is easier for Mandarin speakers. F. Chen analyzed individual-level data from 76 developed and developing countries. This data includes people's economic decisions, such as whether they saved any money last year, the languages they speak at home, demographics (人口统计资料), and cultural factors such as 'saving is an important cultural value for me.' He also analyzed individual-level data on people's retirement assets, smoking and exercising habits, and general health in older age. Lastly, he analyzed national-level data that includes national savings rates, country GDP and GDP growth rates, country demographics, and proportions of people speaking different languages. G. People's savings rates are affected by various factors such as their income, education level, age, religious connection, their countries' legal systems, and their cultural values. After those factors were accounted for, the effect of language on people's savings rates turned out to be big. Speaking a language that has obligatory future markers, such as English, makes people 30 percent less likely to save money for the future. This effect is as large as the effect of unemployment. Being unemployed decreases the likelihood of saving by about 30 percent as well. H. Similar analyses showed that speaking a language that does not have obligatory future markers, such as Mandarin, makes people accumulate more retirement assets, smoke less, exercise more, and generally be healthier in older age. Countries' national savings rates are also affected by language. Having a larger proportion of people speaking languages that does not have obligatory future markers makes national savings rates higher. I. At a more practical level, researchers have been looking for ways to help people act in accordance with their long-term interests. Recent findings suggest that making the future feel closer to the present might improve future-oriented behavior. For instance, researchers recently presented people with renderings of their future selves made using age-progression algorithms (算法) that forecast how physical appearances would change over time. One group of participants saw a digital representation of their current selves in a virtual mirror, and the other group saw an age-morphed version of their future selves. Those participants who saw the age-morphed version of their future selves allocated more money toward a hypothetical savings account. The intervention brought people's future to the present and as a result they saved more for the future. J. Chen's research shows that language structures our future-related thoughts. Language has been used before to alter time perception with surprising effects. Ellen Langer and colleagues famously improved older people's physical health by simple interventions including asking them to talk about the events of twenty years ago as if it they were happening now. Talking about the past as if it were the present changed people's mindsets and their mindsets affected their physical states. Chen's research points at the possibility that the way we talk about the future can shape our mindsets. Language can move the future back and forth in our mental space and this might have dramatic influences on our judgments and decisions.

单选题 The phrase almost completes itself: midlife crisis. It's the stage in the middle of the journey when people feel youth vanishing, their prospects narrowing and death approaching. There's only one problem with the cliché(套话). It isn't true. 'In fact, there is almost no hard evidence for midlife crisis other than a few small pilot studies conducted decades ago,' Barbara Hagerty writes in her new book, Life Reimagined. The vast bulk of the research shows that there may be a pause, or a shifting of gears in the 40s or 50s, but this shift 'can be exciting, rather than terrifying'. Barbara Hagerty looks at some of the features of people who turn midlife into a rebirth. They break routines, because 'autopilot is death'. They choose purpose over happiness—having a clear sense of purpose even reduces the risk of Alzheimer's disease. They give priority to relationships, as careers often recede (逐渐淡化). Life Reimagined paints a picture of middle age that is far from gloomy. Midlife seems like the second big phase of decision-making. Your identity has been formed; you've built up your resources; and now you have the chance to take the big risks precisely because your foundation is already secure. Karl Barth described midlife precisely this way. At middle age, he wrote, 'the sowing is behind; now is the time to reap. The run has been taken; now is the time to leap. Preparation has been made; now is the time for the venture of the work itself.' The middle-aged person, Barth continued, can see death in the distance, but moves with a 'measured haste' to get big new things done while there is still time. What Barth wrote decades ago is even truer today. People are healthy and energetic longer. We have presidential candidates running for their first term in office at age 68, 69 and 74. A longer lifespan is changing the narrative structure of life itself. What could have been considered the beginning of a descent is now a potential turning point—the turning point you are most equipped to take full advantage of.

单选题 The planet is getting lusher, and we are responsible. Carbon dioxide generated by human activity is stimulating photosynthesis (光合作用) and causing a beneficial greening of the Earth's surface. For the first time, researchers claim to have shown that the increase in plant cover is due to this 'CO2 fertilization effect' rather than other causes. However, it remains unclear whether the effect can counter any negative consequences of global warming, such as the spread of deserts. Recent satellite studies have shown that the planet is harboring more vegetation overall, but pinning down the cause has been difficult. Factors such as higher temperatures, extra rainfall, and an increase in atmospheric CO2—which helps plants use water more efficiently—could all be boosting vegetation. To home in on the effect of CO2, Randall Donohue of Australia's national research institute, the CSIRO in Canberra, monitored vegetation at the edges of deserts in Australia, southern Africa, the US Southwest, North Africa, the Middle East and central Asia. These are regions where there is ample warmth and sunlight, but only just enough rainfall for vegetation to grow, so any change in plant cover must be the result of a change in rainfall patterns or CO2 levels, or both. If CO2 levels were constant, then the amount of vegetation per unit of rainfall ought to be constant, too. However, the team found that this figure rose by 11 per cent in these areas between 1982 and 2010, mirroring the rise in CO2 (Geophysical Research Letters, doi. org/mqx). Donohue says this lends 'strong support' to the idea that CO2 fertilization drove the greening. Climate change studies have predicted that many dry areas will get drier and that some deserts will expand. Donohue's findings make this less certain. However, the greening effect may not apply to the world's driest regions. Beth Newingham of the University of Idaho, Moscow, recently published the result of a 10-year experiment involving a greenhouse set up in the Mojave Desert of Nevada. She found 'no sustained increase in biomass' when extra CO2 was pumped into the greenhouse. 'You cannot assume that all these deserts respond the same,' she says. 'Enough water needs to be present for the plants to respond at all.'

单选题What is it about Americans and their food? They love to eat, but they feel 28 about it afterward. They say they want only the best, but they 29 enjoy junk food. They're fascinated by health and weight loss but face an unprecedented (前所未有的) epidemic of obesity (overweight). Perhaps the answer to this ambivalence (矛盾情节) 30 in their history. The first Europeans came to the continent. 31 for new spices (香料) but went in vain. The first cash crop wasn't eaten but smoked. Then there was a 32 , intended to forbid drinking but actually encouraging more creative ways of doing it. The immigrants' experience, too, has been one of inharmony. Do as Romans do means eating what 'real Americans' eat, but the nation's food has come to be 33 by imports—pizza, say, or hot dogs. And some of the country's most treasured cooking comes from people who arrived here in shackles. Perhaps it should come as no 34 then that food has been a medium for the nation's defining struggles, whether at the Boston Tea Party or the sit-ins at southern lunch counters. It is 35 to their concepts of health and even morality whether one gives up alcohol for religious reasons or avoids meat for political results. But strong opinions have not brought 36 . They are ambivalent about what they put into their mouths. They have become 37 of their foods, especially as they learn more about what the foods contain. A. benefits I. guilty B. certainty J. lies C. competing K. prohibition D. defined L. searching E. doubtful M. seemingly F. essential N. strangely G. fantastic O. surprise H. granted

单选题 Directions: For this part, you are allowed 30 minutes to write an essay on sharing economy. You should start your essay with a brief definition of sharing economy and then comment on its impact. You should write at least 120 words but no more than 180 words. Write your essay on Answer Sheet 1.