高考英语知识点过关培优 易错 难题训练∶阅读理解含答案
备战高考英语知识点过关培优易错试卷训练∶阅读理解含答案(1)
一、高中英语阅读理解1．阅读理解Every year migratory(迁徙的) bats travel from Mexico to Bracken Cave, where they spend the summer consuming insects that would otherwise hungrily eat common food crops. But the bats have been showing up far earlier than they did two decades ago.In a study, scientists at Rothamsted Research, an agricultural laboratory in England, used radar data from 160 U.S. weather stations to analyze activity in the Texas bat colony from 1995 through 2017. They discovered the creatures were leaving their winter quarters in Mexico earlier and reproducing sooner. They were also astonished to find increasing numbers of bats overwintering(过冬) at Bracken Cave instead of heading back to their cold weather quarters in Mexico. Overwintering is a sign that warmer temperatures change the bats' annual rhythms, Rothamsted biologist Phillip Stepanian says.A separate study of migratory bats in Indiana, published last year, found that temperature variations affected arrival and departure times—likewise hinting at the potential influence of climate change. Joy O'Keefe, a biology professor at Indiana State University and co-author of that study, says early arrival at their summer habitats(栖息地) could expose these bats to cold snaps(寒流), and they could freeze to death.Joy O'Keefe and her colleagues also found that changing bat migration times can also clash with rainfall patterns. Many insects that bats eat breed in seasonal lakes and puddles. If the bats arrive too early to benefit from summer rainfall and the resulting abundance of insects they may struggle to feed their pups(幼崽) or skip reproduction altogether, O'Keefe says. She fears this shift could cause Midwestern bats to decrease toward extinction, which would be bad news for humans. "Declines in bat populations could have severe effects for crop success," she says, adding that bats also "control significant disease vectors, such as mosquitoes."However, scientists are not certain that climate change alone is causing the Bracken Cave bat colony to migrate earlier. They have found a direct link between seasonal temperatures and bird migration, but bats are also influenced by factors such as changes in wind speed and direction. And there are other complications. “Bats are mysterious little animals th at move mostly at night and are difficult to observe and track," Stepanian says. "We have this conceptual picture of what might be happening, but really tying it to the cause is the next step."（1）Scientists at Rothamsted Research found that _________.A. bats prefer colder weatherB. bats delay their reproductionC. warming affects bat migrationD. radar can be used to observe bats（2）Joy O'Keefe discovered that _________.A. bats are used to living in rainfall seasonsB. bats' earlier migration might harm farmingC. insects' reproduction helps to spread diseaseD. insects shortage makes bats reproduce earlier（3）What does the last paragraph want to tell us?A. Wind speed and direction affect bats.B. It is difficult to observe and track bats.C. Climate change makes bats migrate earlier.D. Further research on the cause is necessary.（4）What is the best title for the passage?A. Bats' habitatsB. Endangered batsC. Bats' scheduleD. Bats, our good friends【答案】（1）C（2）B（3）D（4）C【解析】【分析】【点评】本文是一篇说明文，作者先提出蝙蝠迁徙提前的这种现象，然后分析了这种现象可能导致的后果，最后分析了可能导致蝙蝠迁徙提前的原因。
高考英语 阅读理解 培优 易错 难题练习(含答案)
一、高中英语阅读理解1．阅读理解One of my favorite hobbies is exchanging old-fashioned, paper-with-a-stamp-on-it postcards with random strangers around the world.The Postcrossing Project was created by Paulo Magalhaes in 2005. He liked getting mails—especially postcards. He thought others did, too—but how could he connect with them? That's when he came up with the idea of an online platform (): There, postcard lovers like me can sign up to send a postcard to someone who has registered online, and receive a postcard in return.Along with a randomly selected address, participants get a unique code to put on the postcard. When the postcard arrives, the recipient registers that code with the site, which then causes the sender's address to be given to another postcrosser in turn. In practice, this means that for nearly every postcard I send (a few get lost in the mail) I get one back. And since I never know who will send me a card or where in the world they live, every trip to the mailbox holds the potential for a wonderful surprise.Privacy-conscious Americans might worry about sharing their address with strangers overseas. But postcrossers are friendly, polite, respectful folks—in more than 450 cards exchanged, I've yet to have a bad experience.On days when the international news is depressing, postcrossing is my comfort. There's nothing like getting a card from a child in China just learning to write in English, or a grandmother in Belarus describing her most recent gardening success to remind me that we truly are members of one global family, far more similar than we are different.It seems like such a small thing to send out a postcard. But as travel and communication technology continue to shrink the world, it's important to remember that it isn't just for diplomats and politicians to represent our country anymore. All of us have the power—and perhaps the responsibility—to be ambassadors, to show the best of your country to the world.And it's good to know that what you need to accomplish this is not necessarily complicated or expensive. It can be as simple as a postcard.（1）Why did Paulo set up ?A. To discuss personal hobbies with strangers.B. To exchange postcards with others in the worldC. To collect different postcards from other countries.D. To provide a platform for communication online.（2）According to the passage, postcrossers __________.A. don't know who will send them postcardsB. are sure to get a postcard back immediatelyC. often choose a receiver's address carefullyD. register every postcard they receive online （3）What did the writer learn from postcrossing?A. The international news is usually depressing.B. Americans are more conscious about privacy.C. Postcrossers sometimes describe their bad experience.D. The whole world is actually a big family.（4）What does the underlined word "this" refer to?A. Choosing a diplomat to represent a country.B. Having the responsibility to be an ambassador.C. Showing the best of your country.D. Shrinking the world with communication technology.【答案】（1）B（2）A（3）D（4）C【解析】【分析】本文是一篇应用文，介绍了网站，一个可以让世界各地的陌生人交换老式的、带有邮票的明信片的网站，由Paulo Magalhaes 在2005年创立。
高考英语培优易错试卷(含解析)之阅读理解及详细答案
一、高中英语阅读理解1．阅读理解A famous Anglican Church stands in a quiet corner of Dunedin in New Zealand's South Island. Built in 1865, it is the city's oldest church still in use. Countless couples have gathered here to marry. It's where morning tears are shared, friendships formed and comfort given during times of loss.As with many churches, its walls are graced with a collection of beautiful stained-glass windows. Known as the "John Allen window", one window portrays the short life of a local man, John Allen, who died in 1915 in the Gallipoli campaign in Turkey.John was the son of Sir James Allen, who as Minister of Defense, helped plan and administer New Zealand's World War I strategy, which saw 100,000 troops sent to fight. With the war over and his son dead, Sir James chose to install a window in the church, with which the Allen family had strong ties.Divided into two parts, one depicts (描绘) St. George, the patron saint (守护神) of soldiers, while the other has an angel of peace, along with the words at the bottom, "John Hugh All Gallipoli, 6th June, 1915". Two trees with local birds on the branches can be seen and a kiwi walks at the bottom- reminders that John was a lover of birds."There are many war memorials in the church," says the church. "However the 'John Allen window' stands out; it touches people because of the beautiful design, the New Zealand birds and because John's story, of a life so full of promise ending tragically in the war, reflects the lives and stories of so many others involved in World War I."（1）What does the word "portrays" in paragraph 2 most probably mean?A. Starts.B. Changes.C. Treasures.D. Represents.（2）Sir James Allen built the "John Allen window" to ______________.A.celebrate the end of World War IB.honor the troops in the Gallipoli campaignC.remember his son's sacrifice to the countryD.show the family's close ties with the church（3）What might be the main theme of the pictures on the window?A.Freedom and equality.B.Peace and war.C.Human and nature.D.Marriage and family.（4）What might be the best title for the text?A.A Brave SoldierB.Window on a LifeC.Cruelty of the WarD.A Grand Church【答案】（1）D（2）C（3）B（4）B【解析】【分析】本文是一篇说明文，介绍了一所教堂中一个被称为"约翰·艾伦之窗"的窗户，上面描绘了一位当地人约翰·艾伦的短暂生命。
高考英语 阅读理解 培优 易错 难题练习(含答案)附详细答案
一、高中英语阅读理解1．阅读理解It was the beginning of 2011. I had just finished filming the first season of Game of Thrones(《权利的游戏》). With almost no professional experience, I had been given the role of Daenerys Targaryen. The show was so successful that young girls would dress themselves up as Daenerys for Halloween.And yet, terrified of the attention, terrified of trying to make good on the faith that the creators had put in me, I worked much harder.On the morning of February 11, 2011, I was getting dressed in a gym when I started to feel a bad headache. I was so exhausted that I could barely put on my sneakers. I tried to ignore the pain, but I couldn't. I reached the toilet and sank to my knees. A woman came to help me. Then everything became unclear. I only remember the sound of an ambulance.That operation lasted three hours. When I woke, the pain was unbearable. After four days, they moved me out of the I.C.U. (重症监护室). But one day when a nurse asked me, as part of a series of cognitive (认知的) exercises, " What's your name?", I couldn't remember my name and I felt terrified: I am an actor; I need to remember my lines. Now, I couldn't recall my name.The phenomenon is called aphasia. Then I was sent back to the I.C.U. and, after about a week, I was able to speak and know my name. And I was also aware that there were people in the beds around me who didn't make it out of the I.C.U. I was continually reminded of just how fortunate I was.I rarely gave a thought to my health. Nearly all I thought about was acting. I thought of myself as healthy. Once in a while, I would get dizzy. When I was fourteen, I had a migraine (偏头痛) that kept me in bed for a couple of days. But it all seemed manageable — part of the stress of being an actor. Now I think I might have been experiencing warning signs of what was to come.Anyway, there is something pleasant about coming to the end of Thrones. And I'm so happy to be here to see the beginning of whatever comes next.（1）The author felt terrified after acting in the first season of Game of Thrones because _____.①she felt nervous about the public attention.②she had been criticized for her lack of experience.③she was experiencing some warning signs of a serious illness.④she wasn't sure if she had perform ed well in Season 1.A. ①④B. ②③C. ①②D. ③④（2）When did the author lose consciousness?A. After she took an operation.B. After a woman came to her rescue in a gym.C. When trying to ignore a headache while working out.D. When knowing many patients wouldn't survive the illness.（3）A patient who is suffering from aphasia ______.A. cannot move his or her bodyB. will fall into serious depressionC. must undergo brain surgery at onceD. is not able to remember things from the past （4）What can you infer from the end of the passage?A. The author feels very lucky to be an actress.B. The author is quite confident about her role.C. The author can't go on acting due to the illness.D. The author will pay more attention to her health.【答案】（1）A（2）B（3）D（4）D【解析】【分析】本文是一篇记叙文，作者讲述了自己在作为一名演员对待工作非常认真努力却忽视了自己的身体健康，直到有一天她晕倒并进了重症病房接受治疗，她才意识到要重视身体健康。
高考英语培优 易错 难题(含解析)之阅读理解含详细答案
一、高中英语阅读理解1．阅读理解Researchers in Australia have discovered an effective new method to capture the atmospheric carbon dioxide that is damaging our planet and transform it into something solid, making it much easier to store.Carbon capture isn't new, but previous methods call for the gas to be compressed into liquid and then injected underground. Widespread usage of that technology has been locked by economic and environmental concerns due to possible leaks. Instead, in a study published in Nature Communications, the group details their sustainable and cost-effective plan for transforming CO2 into coal.This new process involves a liquid metal catalyst(催化剂)that is efficient in conducting electricity. CO2gas is dissolved in a container with some liquid. Once electricity charge is introduced, the CO2 begins to turn into solid pieces of carbon, which can be collected and stored. What makes this particularly unique is that the entire process can occur at room temperature. Previous experiments have only shown a gas to solid conversion at extremely high temperature, which made it impossible on a large scale. Now, the researchers are hoping that their work will be used to create even further when it comes to carbon storage.In an interesting side benefit, the solid carbon also works as an electrode(焊条), which opens up a world of possibilities. "A side benefit of the process is that the carbon can hold electrical charge, becoming a super battery, so it could potentially be used as a part in future vehicles," explains Dr. Dorna Estrafilzadeh, a researcher. "The process also produces fuel as a by-product, which could also have industrial applications."（1）What can we know about the previous carbon capture methods?A. People have to inject liquid to the gas.B. The previous methods can be done easily.C. The previous methods are not very popular.D. People have widely accepted previous methods.（2）What is the special part of the new method?A. It needs electricity to make the process efficient.B. It can be done in any kind of container.C. It doesn't need extreme temperature.D. It can produce much solid carbon.（3）What can we infer from the last paragraph?A. The method will make fossil oil disappear.B. The method will influence the future industry.C. The method will make developed countries more powerful.D. The method will be used to make new vehicles.（4）What is the best title for the passage?A. How to change carbon into CO2.B. A new carbon capture technology.C. A new technology to get useful carbon.D. Australia makes the world cleaner than before.【答案】（1）C（2）C（3）B（4）B【解析】【分析】本文是一篇说明文，介绍了一种新的碳捕获技术的原理，优点和对未来工业的影响。
高考英语 阅读理解 培优 易错 难题练习(含答案)及答案解析
一、高中英语阅读理解1．阅读理解Nhon Ly, a 55-year-old Vietnamese-born professional bodybuilder from California has been awarded the "real-life Master Roshi" for his unbelievable similarity to the popular Dragon Ball Z anime(日本动漫) character.Ly certainly doesn't look like any other typical 55-year-old man. In fact, he looks a lot better than most guys in their 20s, with his lean(瘦且健康的), strong muscles and youthful attitude. But he's absolutely not the only 50-something man who has the strong muscle in the world. What really sets Nhon Ly apart from all the rest is his unbelievable similarity to Dragon Ball Z character Master Roshi, also known as the Turtle Hermit, in his "final form". And he apparently liked the comparison so much that he even set his Instagram handle as @master_ roshi_ real_ life.According to Madness Media, Ly immigrated to the United States in 1980, at the age of 16. He got a job as a pedicurist(修脚师) at a nail salon, and worked his way up to salon owner. Although he has achieved so much, bodybuilding has always been his biggest love. He has competed in several professional bodybuilding events, with his most notable results being the 4th place at the 2011 US Championship, the 7th place at the 2012 edition, and the 5th place at the 2015 Nationals.Even at 55, Nhon Ly continues to train hard in the gym in order to keep his Master Roshi look. He also likes to share photos and videos with his 40,000 fans, many of whom are Dragon Ball Z fans. They routinely post a large quantity of comments, thanking him for training Goku, who is the main character in Dragon Ball media, and asking him to train them in the art of bodybuilding.（1）Why is Nhon Ly called "real-life Master Roshi"?A. He looks extremely similar to Master Roshi.B. He is quite good at training people like Goku.C. He has the same life stories as Master Roshi.D. He holds a special attitude to Dragon Ball Z.（2）How does Nhon Ly feel about his "new name"?A. He finds it typical yet silly.B. He thinks it can be popular.C. He is fond of it very much.D. He considers it embarrassing.（3）Which of the following words can best describe Nhon Ly?A. Confident and wealthy.B. Creative and ambitious.C. Athletic and hardworking.D. Healthy and generous.（4）What can be a suitable title for the text?A. Success Comes From Continuous Efforts and DreamsB. Great Achievements of an Old but Still Positive AthleteC. Unbelievable Life Experiences of an Anime CharacterD. A 55-year-old Man Is Known for Looking Like Master Roshi【答案】（1）A（2）C（3）C（4）D【解析】【分析】本文是一篇记叙文，55岁的职业健美运动员尼汉·莱因其与流行的《龙珠Z》中的动画人物龟仙人看起来相像而被授予“现实生活版的龟仙人”的称号。
高考英语阅读理解(大题培优 易错 难题)含答案(1)
一、高中英语阅读理解1．阅读理解The age of adulthood is by definition arbitrary. If everyone matured at the same, fixed rate, it wouldn't be a human process. Indeed, maturation happens at varying speeds across different categories within the same individual, so I'd say I was easily old enough to vote at 16, but nobody should have given me a credit card until I was 32, and I've got the county court judgment to prove it.However, we broadly agree that there's a difference between a child and an adult, even if we might argue about the transition point. So the political theorist David Runciman's view that six-year-olds should be allowed to vote goes against any standard argument about the age of civic responsibility. Nobody would say that a six-year-old could be held criminally responsible, could be sent to war, could be capable of consent, could be given responsibility for anything. So allowing them the vote—along with, unavoidably, seven-year-olds who are even sillier, if anything—is quite an amusing proposal.Runciman's argument is that this is the only way to rebalance political life, which is currently twisted in favor of the old, who don't (he added) ever need to demonstrate mental capacity, even long after they've lost it.The first part of his case is self-evident: pensions are protected while children's centers are closed, concepts such as sovereignty (最高权威) are prioritized over the far more urgent business of the future: climate change. Nostalgia (怀念) for a past the young wouldn't even recognize plays a central role, which is completely unfair.Most of the arguments against giving six-year-olds a vote are that children would end up voting for something damaging and chaotic, if someone made unrealistic promises to them, which could never be realized. Well, it's not children's fault.Having said that, children do tend towards the progressive, having a natural sense of justice (which kicks in at the age of six months, psychologists have shown, by creating scenes of great unfairness to babies, and making them cry) and an underdeveloped sense of self-interest. My kid, when he was six, made quite a forceful case against private property, on the basis that, since everybody needed a house, they shouldn't cost money, because nobody would want anyone else not to have one. Also, food should be free. It was a kind of pre-Marx communism, where you limit the coverage of the market to only those things that you wouldn't mind someone else not having.On that particular day, when we were registered as voters, my kid was quite far to the left of me, but in the normal run of things, we're united, which brings us to the point of the problem: children obey you on almost nothing, but they do seem to believe in your politics until they're adolescent. So giving kids the vote is really just a way of giving parents extra votes. And what can stop us having even more children, once there's so much enfranchisement (选举权) in it for us? Now, if parents could be trusted to use their influence wisely, and hammer into children the politics it will take to assure a better future, then I wouldn't necessarily have a problem with that, apart from, obviously, that culture is already wildly twisted towards parents, and I can imagine afew non-parents boiling with fierce anger. But that's not worth talking about anyway, because parents can't be trusted, otherwise we'd all already vote Green(绿党).In short: no, six-year-olds should not get the vote; but while we're here, if any votes come up in the near future, which will have an impact on the next five decades of British political life, alongside EU migrants, 16-year-olds certainly should be enfranchised.（1）The author refers to his age of adulthood to prove that ________.A. certain rights are granted at different stages of lifeB. there's a common standard for the age of adulthoodC. people mature at different rates in various aspectsD. a credit card is more difficult to get than the vote（2）People reject David Runciman's proposal because ________.A. they believe children are far from mature in many waysB. they are uncertain whether children can assume responsibilityC. they know the age to get the vote is not to be questionedD. they don't think a child can grow into adulthood earlier（3）What is the base for David Runciman's argument?A. Public ignorance of children's abilities.B. Inequalities of opportunity.C. A cultural preference for the old.D. The imbalance in political life.（4）The author talks about his kid to indicate that ________.A. children are in favor of a just society and tend to be idealisticB. children are innocent and don't want to be involved in politicsC. children are simple-minded and can fall for an adult's trickD. children are good-natured and like to help people in need（5）The author thinks allowing children the vote may lead to ________.A. twisted cultureB. parents' objectionsC. misuse of rightsD. unusual maturation （6）What is the main point of the passage?A. There is a difference between adults and children.B. Allowing children the vote is not altogether absurd.C. The definition of adulthood is quite controversial.D. Parents should introduce politics to their children.【答案】（1）C（2）A（3）D（4）A（5）C（6）B【解析】【分析】本文是一篇议论文，讲述了儿童成熟的速度是不同，所以作者认为允许儿童投票的提议并不完全是荒谬的，如果将对未来50年的英国政治生活产生影响，16岁的孩子应该被授予选举权。
高考英语 阅读理解 培优 易错 难题练习(含答案)附答案
一、高中英语阅读理解1．阅读理解China Small Group ToursTour Route 1: 11 Days Private Beijing – Lhasa – Xi'an – ShanghaiTour Highlights:Must-see sights in China－the Great Wall, Forbidden City, Terracotta WarriorsFollow us on a Buddhist pilgrimage to Tibet & appreciate the profound cultureHave a leisurely walk or an exciting bicycle ride on the time-honored City Wall of Xi'anView the soaring city skylines and feel the pulse of modern ShanghaiFrom $ 2, 459 per personTour Route 2: 11 Days Private Bejing –Xi'an –Chonqing –Yangtze River Cruise –Yichang –ShanghaiTour Highlights:Must-see sights in China－the Great Wall, Forbidden City, Terracotta WarriorsTry biking on the Ming Dynasty City Wall of Xi' an, or tour by electric carEnjoy the Three Gorges scenery on Yangtze River & feel totally relaxedFrom $ 1, 879 per personTour Route 3: 12 Days Private Beijing – Shanghai – Xi'an – Guilin – Yangshuo – Guilin – Hong KongTour Highlights:Must-see sights in China－the Great Wall, Forbidden City, Terracotta WarriorsExperience the Bund, classical garden, modern and old in contrast in ShanghaiFeel the lively atmosphere & explore busy markets freely in Hong KongWalk into a local family, learn to cook Chinese food & dine with the hosts in their homeFrom $ 2, 499 per personTour Route 4: 12 Days Private Beijing – Xi'an – Chengdu – Guilin – ShanghaiTour Highlights:Must-see sights in China－the Great Wall, Forbidden City, Terracotta Warriors, Giant PandasCome to Chengdu，the hometown of giant pandas to visit and observe the cute creatureCruise on the meandering Li River & admire Guilin landscapeWalk into a local Chinese family, interact & dine with the hosts in their homeFrom $2, 079 per person（1）What do Tour Route 1 and Tour Route 2 have in common?A. They have cycling activities.B. They include a visit to Tibet.C. Visitors enjoy the Three Gorges scenery.D. Visitors pay the same amount of money.（2）What is special about Tour Route 2?A.Tourists can travel by bike.B.Tourists can visit a huge dam.C.Tourists can dine with a family.D.It is the most expensive of the four.（3）Where can visitors enjoy China's rare animals?A.Tour Route 1.B.Tour Route 2.C.Tour Route 3.D.Tour Route 4.【答案】（1）A（2）B（3）D【解析】【分析】本文是一篇应用文，介绍了四条旅游路线。
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一、高中英语阅读理解1．（2019•天津）阅读理解How does an ecosystem（生态系统）work? What makes the populations of different species the way they are? Why are there so many flies and so few wolves? To find an answer, scientists have built mathematical models of food webs, noting who eats whom and how much each one eats.With such models, scientists have found out some key principles operating in food webs. Most food webs, for instance, consist of many weak links rather than a few strong ones. When a predator（掠食动物）always eats huge numbers of a single prey（猎物）, the two species are strongly linked; when a predator lives on various species, they are weakly linked. Food webs may be dominated by many weak links because that arrangement is more stable over the long term. If a predator can eat several species, it can survive the extinction（灭绝）of one of them. And if a predator can move on to another species that is easier to find when a prey species becomes rare, the switch allows the original prey to recover. The weak links may thus keep species from driving one another to extinction.Mathematical models have also revealed that food webs may be unstable, where small changes of top predators can lead to big effects throughout entire ecosystems. In the 1960s, scientists proposed that predators at the top of a food web had a surprising amount of control over the size of populations of other species---including species they did not directly attack.And unplanned human activities have proved the idea of top-down control by top predators to be true. In the ocean, we fished for top predators such as cod on an industrial scale, while on land, we killed off large predators such as wolves. These actions have greatly affected the ecological balance.Scientists have built an early-warning system based on mathematical models. Ideally, the system would tell us when to adapt human activities that are pushing an ecosystem toward a breakdown or would even allow us to pull an ecosystem back from the borderline. Prevention is key, scientists says because once ecosystems pass their tipping point（临界点）, it is remarkably difficult for them to return.（1）What have scientists discovered with the help of mathematical models of food webs？A. The living habits of species in food webs.B. The rules governing food webs of the ecosystems.C. The approaches to studying the species in the ecosystems.D. The differences between weak and strong links in food webs.（2）A strong link is found between two species when a predator______.A. has a wide food choiceB. can easily find new preyC. sticks to one prey speciesD. can quickly move to another place（3）What will happen if the populations of top predators in a food web greatly decline？A. The prey species they directly attack will die out.B. The species they indirectly attack will turn into top predators.C. The living environment of other species will remain unchanged.D. The populations of other species will experience unexpected changes.（4）What conclusion can be drawn from the examples in Paragraph 4？A. Uncontrolled human activities greatly upset ecosystems.B. Rapid economic development threatens animal habitats.C. Species of commercial value dominate other species.D. Industrial activities help keep food webs stable.（5）How does an early-warning system help us maintain the ecological balance？A. By getting illegal practices under control.B. By stopping us from killing large predators.C. By bringing the broken-down ecosystems back to normal.D. By signaling the urgent need for taking preventive action.【答案】（1）B（2）C（3）D（4）A（5）D【解析】【分析】本文是一篇说明文，介绍了借助食物网的数学模型，科学家们发现了一些在食物网运营的关键原则。
科学家们说;因为一个生态系统越过了它的临界点，它们很难再回来。
该系统将告诉我们何时适应人类活动，这些活动正将生态系统推向崩溃，或者甚至允许我们将生态系统从边缘拉回来，预防是关键。
（1）考查细节理解。
根据第二段中的“With such models, scientists have found out some key principles operating in food webs.”可知，借助食物网的数学模型，科学家们发现了食物网中的一些关键原则。
故选B。
（2）考查细节理解。
根据第二段中的“When a predator(掠食动物) always eats huge numbers of a single prey(猎物)，the two species are strongly linked”可知，当捕食者总是吃大量的单一猎物，这两个物种是紧密相连的。
故选C。
（3）考查推理判断。
根据第三段中的“In the 1960s, scientists proposed that predators at the top of a food web had, a surprising amount of control over the size of populations of other species they did not directly attack”可知，处于食物网顶端的食肉动物对它们没有直接攻击的其他物种的种群数量有着惊人的控制，由此可推断出，如果食物链顶级食肉动物的数量大大下降，其他物种的种群将经历意想不到的变化。
故选D。
（4）考查推理判断。
根据最后一段中的“Ideally the system would tell us when to adapt human activities that are pushing an ecosystem toward a breakdown or would even allow us to pull an ecosystem back from the borderline”可知，人类过度的活动会将生态系统推向崩溃，由此可推断出，不受控制的人类活动极大地破坏了生态系统。