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共用题干
第二篇

Are These Food Safe to Eat?

Traditionally,in plant breeding,there are crossing varieties of the same species in ways they could cross naturally.For example,disease-resistant varieties of wheat have been crossed with highyield wheat to combine these properties.This type of natural gene exchange is safe and fairly predictable.
Genetic engineering(GE)makes it possible to exchange genes between unrelated species that cannot exchange genes with each other in a natural way.GE can involve the exchange of genes be-tween vastly different species一e.g. putting scorpion toxin genes into maize or fish antifreeze genes into tomatoes.It is possible that a scorpion toxin gene,even when it is in maize DNA,will still get the organism to produce scorpion toxin一but what other effects may it have in this alien environment? We have already realized this problem一adding human growth hormone genes to pigs certainly makes them grow一but it also gives them arthritis and makes them cross-eyed,which was entirely out of expectation.
It won't be difficult to find out,for example,that the gene for human intelligence will not have the same effect if it is inserted into cabbage DNA as it had in human DNA一but what side-effect would it have?In other words,is genetically modified(GM)food safe to eat?The answer is that no-body knows because long-term tests have not been carried out.
Those companies who want a GM product approved in the UK or USA are required to provide regulatory bodies with results of their own safety tests.Monsanto's soya beans were apparently fed to fish for 10 weeks before being approved.There was no requirement for independent testing,for longterm testing,for testing on humans or testing for specific dangers to children or allergic people.
The present opinion of the British Government is that"There is no evidence of long-term dangers from GM foods."In the US,the American Food and Drug Administration is now being prosecuted for covering up research that suggested possible risks from GM foods.

What can we infer from the passage?
A:The British Government keeps silent when it comes to GM foods.
B:It's safe to buy GM soya beans in the supermarket.
C:The American Food and Drug Administration now set up some regulations for genetically modified plants.
D:Genetic Engineering is sometimes dangerous and rather unpredictable.

参考答案

参考解析
解析:本题是细节判断题。题干是:哪种自然基因交换既安全又具有相当的可预见性?选B的依据是第一段第一句和最后一句:" Traditionally , in plant breeding , there are crossing varieties of the same species in ways they could cross naturally.""This type of natural gene exchange is safe and fairly predictable.”传统的植物培育方法,是依照植物自然杂交的方式进行相同物种的人工杂交。这种自然的基因交换既安全,又具有相当的可预见性。这说明选项B, 传统植物培育中的自然基因交换,是正确答案。
本题是细节考查题。题干是:根据原文,如下关于转基因产品的说法哪个是正确的?选C的依据是第三段第一句:"…… for example , that the gene for human intelligence will not have the same effect if it is inserted into cabbage DNA as it had in human DNA.”例如,人类的智力基因在人体DNA内和注入卷心菜DNA后的作用是不同的。所以选项C符合题目要求,是正确答案。
本题是细节推理题。题干是:根据原文能推断出如下哪个句子?选D的依据是第二段和第四段的最后一句:"… which was entirely out of expectation." " There was no requirement for independent testing,for long一term testing,for testing on humans or testing for specific dangers to children or allergic people.”而这一切是完全无法预测的。目前,尚无要求对转基因产品进行独立测试、长期测试、人体测试,或者就其对儿童或过敏者所造成的特定危险进行测试。选项D,基因工程有时有危险且难以预测,是对原文这两个事实的总结,是正确答案。
本题是细节判断题。题干是:作者可能持有的对于转基因产品的态度是什么?选B的依据是:作者在文中用来说明的事实通常和基因工程的危险和不确定性相关,所以选项B,拒绝的,是正确答案。
本题考查对于后文内容的预判能力。题干是:以下对文章的阐述哪个是正确的?选A的依据是全文第四段的第一句:" Those Companies who want a GM product approved in the UK or USA are required to provide regulatory bodies with results of their own safety tests.”在英国或者美国,如果一个公司希望其转基因产品获得批准,它必须向管理机构提供本公司转基因产品安全测试的结果。这与选项A中谈到的内容相符:如果一个公司能向管理机构提供本公司转基因产品安全测试的结果,就能从英国或美国获得转基因产品的许可。
更多 “共用题干 第二篇Are These Food Safe to Eat?Traditionally,in plant breeding,there are crossing varieties of the same species in ways they could cross naturally.For example,disease-resistant varieties of wheat have been crossed with highyield wheat to combine these properties.This type of natural gene exchange is safe and fairly predictable.Genetic engineering(GE)makes it possible to exchange genes between unrelated species that cannot exchange genes with each other in a natural way.GE can involve the exchange of genes be-tween vastly different species一e.g. putting scorpion toxin genes into maize or fish antifreeze genes into tomatoes.It is possible that a scorpion toxin gene,even when it is in maize DNA,will still get the organism to produce scorpion toxin一but what other effects may it have in this alien environment? We have already realized this problem一adding human growth hormone genes to pigs certainly makes them grow一but it also gives them arthritis and makes them cross-eyed,which was entirely out of expectation.It won't be difficult to find out,for example,that the gene for human intelligence will not have the same effect if it is inserted into cabbage DNA as it had in human DNA一but what side-effect would it have?In other words,is genetically modified(GM)food safe to eat?The answer is that no-body knows because long-term tests have not been carried out.Those companies who want a GM product approved in the UK or USA are required to provide regulatory bodies with results of their own safety tests.Monsanto's soya beans were apparently fed to fish for 10 weeks before being approved.There was no requirement for independent testing,for longterm testing,for testing on humans or testing for specific dangers to children or allergic people.The present opinion of the British Government is that"There is no evidence of long-term dangers from GM foods."In the US,the American Food and Drug Administration is now being prosecuted for covering up research that suggested possible risks from GM foods.What can we infer from the passage?A:The British Government keeps silent when it comes to GM foods.B:It's safe to buy GM soya beans in the supermarket.C:The American Food and Drug Administration now set up some regulations for genetically modified plants.D:Genetic Engineering is sometimes dangerous and rather unpredictable.” 相关考题
考题 共用题干 第三篇On the Trail of the Honey BadgerOn a recent field trip to the Kalahari Desert,a team of researchers learnt a lot more about honey badgers(獾).The team employed a local wildlife expert,Kitso Khama,t& help them locate and follow the badgers across the desert.Their main aim was to study the badgers'movements and behaviour as discreetly (谨慎地)as possible,without frightening them away or causing them to change their natural behaviour. Theyalso planned to trap a few and study them close up before releasing them.In view of the animal's reputation, this was something that even Khama was reluctant to do. "The problem with honey badgers is that they are naturally curious animals, especially when they see something new,"he says. "That, combined with their unpredictable nature,can be a dangerous mixture. If they sense you have food ,for example , they won't be shy about coming right up to you for something to eat. They're actually quite sociable creatures around humans ,but as soon as ther feel they might be in danger, they can become extremely vicious(凶恶的).Fortunately this is rare ,but it does happen."The research confirmed many things that were already known.As expected , honey badgers ate any crea- tures they could catch and kill. Even poisonous snakes , feared and avoided by most other animals,were not safe from them. The researchers were surprised , however, by the animal' s fondness for local melons , probably because of their high water content. Previously researchers thought that the animal got all of its liquid require- ments from its prey(猎物).The team also learnt that , contraryto previous research findings, the badgers oc- casionauy formed loose famiiy groups. They were also able to confirm certain results Irom previous research,including the fact that female badgers never socialised with each other.Following some of the male badgers was a challenge,since they can cover large distances in a short space of time. Some hunting territories cover more than 500 square kilometers. Although they seem happy to share these territories with other males,there are occasional fights over an important food source, and male badgers can be as aggressive towards each other as they are towards other species.As the badgers became accustomed to the presence of people , it gave the team the chance to get up close to them without being the subject of the animals'curiosity-or their sudden aggression. The badgers'eating patterns, which had been disrupted,returned to normal. It also allowed the team to observe more closely some of the other creatures that form working associations with the honey badger, as these seemed to adopt the badgers' relaxed attitude when near humans. Which of the following is a typeal feature of male badgers?A: They don't run very quickly.B: They defend their terl'ttory from other badgers. C: They hunt over a very large area. D: They are more aggressive than females.

考题 Primer on Smell In addition to bringing out1 the flavor of food, what does the sense of smell do for us ? Smell “gives us information about place, about where we are,” says Randall Reed, a Johns Hopkins University professor whose specialty is the sense of smell. ___1___ “Whether we realize it or not, we collect a lot of information about who is around us based on smell,” says Reed. Even at a distance, odors can warn us of2 trouble — spoiled food, leaking gas, or fire. “It’s a great alert,” offers Donald Leopold, a doctor at Johns Hopkins. For example, if something in the oven is burning, everyone in the house knows it. With just a simple scent, smell can also evoke very intense emotion. Let’s say, for example, that the smell is purple petunias. ___2___ Now let’s imagine that your mother died when you were three, and she used to have a flower garden. You wouldn’t need to identify the smell or to have conscious memories of your mother or her garden. You would feel sad as soon as you smelled that spicy odor. Compared with3 animals, how well do people detect smelts ? That depends on what you mean by “how well”. We are low on receptor cells : current estimates say that humans have roughly five million smell-receptor cells, about as many as a mouse. ___3___ Reed says that, across species, there is a relatively good correlation between the number of receptor cells and how strong the sense of smell is. “You can hardly find the olfactory bulb in a human brain —— it’s a pea-sized object. In a mouse, it’s a little bigger. It’s bean-sized in a rat, about the size of your little finger in a rabbit, and the size of your thumb in a bloodhound.” Does that mean that our sense of smell is not very acute ? Not exactly. While we may not have the olfactory range of other creatures, the receptors we do have are as sensitive as those of any animal. ___4___ A trained “nose”, such as that of a professional in the perfume business, can name and distinguish about 10,000 odors. Reed says that a perfume expert can sniff a modem scent that has a hundred different odorants in it, go into the lab, and list the ingredients. “In a modest amount of time, he comes back with what to you or me would smell like a perfect imitation of that perfume. It’s amazing.” What happens to4 our sense of smell as we age ? Many people continue to have good olfactory function as they get older. ___5___ Leopold says that smell is generally highest in childhood, stays the same from the teens through the 50s, and drops starting at about 60 for women and 65 for men. “The average 80-year-old is only able to smell things half as well as the average 20-year-old,” says Leopold. 词汇: scent /sent/ n. 气味,香味 petunia /p 'tju:ni / n. 喇叭花 olfactory / l'f kt( )ri/ adj. 嗔觉的,味道的 sniff /snif/ v. 嗅,闻,用力吸 注释: 1. bring out:使……显出,使……变得明显 2. warn of:发出关于……的警告。warn sb. of sth.:警告某人某事 3. compare with:与……相比 4. happen to:发生于,发生在 练习: A These flowers have a rich spiciness that no other petunia has. B Odors, or smells, can warn us about trouble. C That’s not the rule, however. D And smell tells us about people. E We can also think, and we make conscious (and successful) efforts to tell the difference between one smell and another. F A rat has some 10 million, a rabbit 20 million, and a bloodhound 100 million.

考题 Her comments about men are utterly ridiculous.A:slightly B:partly C:faintly D:completely

考题 共用题干 第二篇A Phone That Knows You're BusyIt's a modern problem : you're too busy to be disturbed by incessant(连续不断的) phone calls so you turn your cellphone off.But if you don't remember to turn it back onwhen you're less busy,you could miss some important calls.If only the phone knew when it was wise to interrupt you,you wouldn't have to turn it off at all.Instead,it could let calls through when you are not too busy.A bunch of behavior sensors(传感器)and a clever piece of software could do just that,by analyzing your behavior to determine if it's a good time to interrupt you.If built into a phone,the system may decide you're too busy and ask the caller to leave a message or ring back later.James Fogarty and Scott Hudson at Camegie Mellon University in Pennsylvania based their system on tiny microphones,cameras and touch sensors that reveal body language and activity.First they had to study different behaviors to find out which ones strongly predict whether your mind is interrupted.The potential"busyness"signals they focused on included whether the office doors were left open or closed,the time of day,if other people were with the person in question, how close they were to each other,and whether or not the computer was in use.The sensors monitored these and many other factors while four subjects were at work. At random intervals,the subjects rated how interruptible they were on a scale ranging from "highly interruptible"to"highly not-interruptible".Their ratings were then correlated with the various behaviors. " It is a shotgun(随意的)approach: we used all the indicators we could think of and then let statistics find out which were important,"says Hudson.The model showed that using the keyboard,and talking on a landline or to someone else in the office correlated most strongly with how interruptible the subjects judged themselves to be.Interestingly,the computer was actually better than people at predicting when someone was too busy to be interrupted.The computer got it right 82 percent of the time,humans 77 percent.Fogarty speculates that this might be because people doing the interrupting are inevitably biased towards delivering their message,whereas computers don't care.The first application for Hudson and Fogarty's system is likely to be in an instant messaging system,followed by office phones and cellphones. "There is no technological roadblock(障碍)to it being deployed in a couple of years,"says Hudson.Scientists at Camegie Mellon University tried to find outA:why office doors were often left open.B:when it was a good time to turn off the computer.C:what questions office workers were bothered with.D:which behaviors could tell whether a person was busy.

考题 共用题干 “Liquefaction” Key to Much of Japanese Earthquake DamageThe massive subduction zone earthquake in Japan caused a significant level of soil“liquefaction” that has surprised researchers with its1severity,a new analysis shows.“We've seen localized examples of soil liquefaction as extreme as this before,but the distance and2of damage in Japan were unusually severe,”said Scott Ashford,a professor of geotechnical engineering at Oregon State University.“Entire structures were tilted and sinking into the sediments,”Ashford said.“The shifts in soil destroyed water,drain and gas pipelines,crippling the utilities and infrastructure these communities need to3. We saw some places that sank as much as four feet.”Some degree of soil liquefaction is common in almost any major earthquake. It's a phenomenon in which soils soaked with water,particularly recent sediments or sand,can lose much of their4and flow during an earthquake. This can allow structures to shift or sink or5.But most earthquakes are much6than the recent event in Japan,Ashford said. The length of the Japanese earthquake,as much as five minutes,may force researchers to recon-sider the extent of liquefaction damage possibly occurring in situations such as this.“With such a long-lasting earthquake,we saw7structures that might have been okay after 30 seconds just continued to sink and tilt as the shaking continued for several more minutes,”he said.“And it was clear that younger sediments,and especially areas built on8filled ground,are much more vulnerable.”The data provided by analyzing the Japanese earthquake,researchers said,should make it possible to improve the understanding of this soil9and better prepare for it in the future.Ashford said it was critical for the team to collect the information quickly,10damage was removed in the recovery efforts.“There's no doubt that we'll learn things from what happened in Japan that will help us to reduce risks in other similar11,”Ashford said.“Future construction in some places may make more use of techniques known to reduce liquefaction,such as better compaction to make soils dense,or use of reinforcing stone columns.”Ashford pointed out that northern California have younger soils vulnerable to liquefac-tion一on the coast,near river deposits or in areas with filled ground. The“young”sedi-ments,in geologic terms,may be those12within the past 10,000 years or more. In Ore-gon,for instance,that describes much of downtown Portland,the Portland International Airport and other cities.Anything13a river and old flood plains is a suspect,and the Oregon Department of Transportation has already concluded that 1,100 bridges in the state are at risk from an earthquake.Fewer than 15 percent of them have been reinforced to14collapse. Japan has suffered tremendous losses in the March 11 earthquake,but Japanese construction15 helped prevent many buildings from collapse一even as they tilted and sank into the ground.8._________A: occasionally B: frequently C: specially D: recently

考题 共用题干 第一篇Forecasting MethodsThere are several different methods that can be used to create a forecast. The method a forecaster chooses depends upon the experience of the forecaster,the amount of information available to the forecaster,the level of difficulty that the forecast situation presents,and the degree of accuracy or confidence needed in the forecast.The first of these methods is the persistence method,the simplest way of producing a forecast.The per- sistence method assumes that the conditions at the time of the forecast will not change.For example,if it is sunny and 87 degrees today,the persistence method predicts that it will be sunny and 87 degrees tomorrow. If two inches of rain fell today,the persistence method would predict two inches of rain for tomorrow. However,if weather conditions change significantly from day to day,the persistence method usually breaks down and is not the best forecasting method to use.The trends method involves determining the speed and direction of movement for fronts,high and low pressure centers , and areas of clouds and precipitation(降水量).Using this information , the forecaster can predict where he or she expects those features to be at some future time.For example,if a storm system is 1,000 miles west of your location and moving to the east at 250 miles per day,using the trends method you would predict it arrive in your area in 4 days.The trends method works well when systems continue to move at the same speed in the same direction for a long period of time.If they slow down,speed up,change intensi- ty,or change directions,the trends forecast will probably not work as well.The climatology(气候学)method is another simple way of producing a forecast. This method involves averaging weather statistics accumulated over many years to make the forecast.For example,if you were using the climatology method to predict the weather for New York City on July 4th,you would go through all the weather data that has been recorded for every July 4th and take an average.The climatology method oniy works well when the weather pattern is similar to that expected for the chosen time of year. If the pattern is quite unusual for the given time of year,the climatology method will often fail.The analog method is a slightly more complicated method of producing a forecast.It involves examining today's forecast scenario(模式)and remembering a day in the past when the weather scenario looked very similar(an analog).The forecaster would predict that the weather in this forecast will behave the same as ii did in the past.The analog method is difficult to use because it is virtually impossible to find a predict ana- log.Various weather features rarely align themselves in the same locations as they were in the previous time. Even small differences between the current time and the analog can lead to very different results.The trends method works well when_________.A:weather features are defined well enoughB:predictions on precipitation are accurateC:weather features are constant for a long period of timeD:the speed and direction of movement are predicable

考题 共用题干 Europa's Watery UnderworldEuropa,one of Jupiter's 63 known moons,looks bright and icy on the surface.But appearances can be deceiving:Miles within its cracked,frigid shell,Europa probably hides giant pools of liquid water. Where scientists find liquid water,they hope to find life as well.Since we can't go diving into Europa's depths just yet,scientists instead have to investigate the moon's surface for clues to what lies beneath.In a new study,scientists investigated one group of strange ice patterns on Europa and concluded that the formations mark the top of an underground pool that holds as much water as the U.S.Great Lakes.Pictures of Europa,which is slightly smaller than Earth's moon,clearly show a tangled,icy mishmash of lines and cracks known as"chaos terrains".These chaotic places cover more than half of Europa. For more than 10 years,scientists have wondered what causes the formations.The new study suggests that they arise from the mixing of vast underground stores of liquid water with icy material near the surface.For scientists who suspect that Europa also may be hiding life beneath its icy surface,the news about the new lake is exciting."It would be great if these lakes harbored life,"Britney Schmidt,a planetary scientist who worked onthe study,told Science News."But even if they didn't,they say that Europa is doing something interesting and active right now."Schmidt,a scientist at the University of Texas at Austin,and her colleagues wanted to know how chaos terrains form.Since they couldn't rocket to Europa to see for themselves,they searched for similar forma- tions here on Earth.They studied collapsed ice shelves in Antarctica and icy caps on volcanoes in Iceland. Those features on Earth formed when liquid water mixed with ice.The scientists now suspect something similar might be happening on Europa:that as water and ice of different temperatures mingle and shift,the surface fractures.This would explain the jumbled ice sculptures."Fracturing catastrophically disrupts the ice in the same way that it causes ice shelves to collapse on Earth,"Schmidt told Science News.She and her team found that the process could be causing chaos terrains to form quickly on Europa.The new study suggests that on this moon,elements such as oxygen from the surface blend with the deep bodies of water. That mixture may create an environment that supports life.The strange ice patterns on Europa are formed as a result of a mixture of liquid water and solid material underground water pool.A:RightB:WrongC:Not mentioned

考题 Many experts remain skeptical about his claims.A:doubtful B:untouched C:certain D:silent

考题 共用题干 Old Man Myths and Realities1.When does a middle-aged man become an old man?Officially,of course,it is when we reach retirement age. But, as we all know, this is a fairly blunt(生硬的)method of decision making. As life expectancy(寿命)increases,retirement planning needs to be changed. This is because being an old man today is very different from what it was a generation or so ago.2.Sixty-five is the new middle-aged man. These days people are talking about the young-old, that is ages 70-75,and those over 75 as the old-old. The young-old frequently continue in good health and maintain strong links with friends and family.The old-old have a much higher chance of poor health and social isolation.3.Although men are living longer,there are still more old women than old men.This fact alone should arouse interest as to why. Relatively little is actually known about why this is the case or about the experiences of the old man.Sure,we are aware that the old man experiences anxiety,financial problems,loneliness,etc.,but that is really about all we know.4.It is usually believed that the old man often complains about their health.In fact,most old man think their health is good even though most are diagnosed with at least one chronic illness.The physical health of the old man is strongly affected by their health behavior when they were younger.A man in his mid-60s is now regarded as______.A:in good healthB:in the pastC:in the wrongD:the old manE:a middle-aged man F: a young man

考题 Guests were scared when the bomb explored.A:frightened B:killed C:endangered D:rescued

考题 共用题干 Men Too May Suffer from Domestic ViolenceNearly three in 10 men have experienced violence at the hands of an intimate(亲密的)partner during their lifetimes,according to one of the few studies to look______(51)domestic violence and health among men."Many men actually do experience domestic violence,although we don't hear about it ______(52),"Dr. Robert J. Reid of the University of Washington in Seattle,one of the authors,told Reuters Health."They often don't tell______(53)we don't ask. We want to message out(传达这样一个信息)to men who______(54)experience domestic violence that they are not alone and there are resources available to______(55)."The researchers asked study participants about physical abuse(伤害)and non-physical ______(56)such as threats that made them______(57)for their safety,controlling behavior (for example,being told who they could associate with and where they could go),and constant name-calling(辱骂).Among men 1 8 to 54 years old,14.2 percent said they had experienced intimate partner______(58)in the past five years,while 6.1 percent reported domestic violence in the previous year.Rates were lower for men 55 and______(59),with 5.3 percent reporting violence in the past five years and 2.4 percent having experienced it in the past 12 months.Overall,30.5 percent of men younger than 55 and 26.5 percent of older men said they had been victims of______(60)violence at some point in their lives.About half of the violence men______(61)was physical.However,the physical violence men reported wasn't as harsh as______(62)suffered by women in a previous study;20 percent to 40 percent of the men rated it as severe,compare to 61 percent of______(63).Men who reported experiencing domestic violence had more emotional and mental problems ______(64)those who had not,especially older men,the______(65)found._________(51)A:by B:atC:on D:for