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The government has set up a working party to look into the case.A:investigate B:study C:solve D:see12-25
共用题干 The Greatest Mystery of WhalesThe whale is a warm-blooded,air-breathing animal,giving birth to its young alive,sucking them-and, like all mammals,originated on land.There are many______(51)of this.Its front flippers（鳍状肢）, used for steering and stability,are traces of feet.Immense strength is______(52)into the great body of the big whales,and in fact most of a whale's body is one gigantic muscle.The blue whale's pulling strength has been estimated______(53) 400 horsepower.One specimen was reported to have towed（拖）a whaling vessel for seven hours at the ______(54)of eight knot（节）.An angry whale will______(55).A famous example of this was the fate of Whaler Essex, ______(56)was sunk off the coast of South America early in the last century.More recently,steel ships have______( 57 ) their plates buckled（使弯曲）in the same way.Sperm whales（抹香鲸）were known to seize the old-time whaleboats in their jaws and crush them.The greatest______(58)of whales is their diving ability.The sperm whale dives to the bottom for his______( 59 ) food , the octopus（章鱼）.In that search he is known to go as far down as 3 , 200 feet, where the______(60)is 1,400 pounds to a square inch.Doing so he will______(61) underwater as long as one hour.Two special skills are involved in this storing up enough______(62) (all whales are air-breathed)and tolerating thern great change in pressure.Just how he does it scientists have not______(63).It is believed that some of the oxygen is stored in a special ______(64)of blood vessels,rather than just held in the lungs.And it is believed that a special kind of oi1 in his head is some sort of a compensating mechanism that______(65)adjusts the internal pressure of his body.But since you can't bring a live whale into the laboratory for study,no one knows just how these things work.56._________A:as B:who C:which D:that09-24
It is important to learn to communicate.A:minor B:crucial C:impossible D:effective09-21
共用题干 The Impact of Antarctic Ozone HoleThe Antarctic ozone（臭氧）hole is changing weather patterns across the Southern Hemisphere （半球）,even affecting the tropics,scientists have concluded. The scientists______(51)the new study added the ozone hole into standard climate models to_______(52)how it might have affected winds and rains. They say rainfall has moved further south towards the pole and the effect has been_______(53)strong over Australia.And of_______(54)interest was the southward of the Southern Hemisphere jet stream. These high一altitude winds are_______(55)to determining weather patterns,in both hemispheres. Much of the cold weather felt in the UK_______(56)the last couple of winters,for example,was caused by blocking of the Northern Hemisphere stream.The team found that overall,the ozone hole has_______(57)in rainfall moving south along with the winds._______(58)there are regional differences,particularly concerning Australia. In terms of the average for that zone,the ozone hole_______(59)about a 10% change一but for Australia,it's about 35%.Their modeling indicated that global warming_______(60)greenhouse gas emissions is also a factor in changing rainfall patterns.Natural climate cycles are also thought to be important here,as different rainfall patterns were _______(61)in the era before ozone depletion（消耗）and late 20th Century warming.Although the_______(62)international organization has significantly checked emissions of harmful substances,they_______(63)for decades in the atmosphere,and so their effects are still being felt.Earlier,and international organization forecast that even the Antarctic ozone hole一which is more severe than its_______(64)in the Northern Hemisphere一should be_______(65)by 2045—2060._________(65)A:repeated B:reproducedC:replaced D:repaired09-21
共用题干 More Than 8 Hours Sleep Too Much of a Good Thing1 Although the dangers of too little sleep are widely known,new research suggests that people who sleep too much may also suffer the consequences.2 Investigators at the University of California in San Diego found that people who clock up 9 or 10 hours each weeknight appear to have more trouble falling and staying asleep,as well as a number of other sleep problems,than people who sleep 8 hours a night. People who slept only 7 hours each night also said they had more trouble falling asleep and feeling re-freshed after a night's sleep than 8-hour sleepers.3 These findings,which DL Daniel Kripke reported in the journal Psychosomatic Medicine,demonstrate that people who want to get a good night's rest may not need to set aside more than 8 hours a night.He added that“it might be a good idea” for people who sleep more than 8 hours each night to consider reducing the amount of time they spend in bed,but cau-tioned that more research is needed to confirm this.4 Previous studies have shown the potential dangers of chronic shortages of sleep一for instance,one report demonstrated that people who habitually sleep less than 7 hours each night have a higher risk of dying within a fixed period than people who sleep more.5 For the current report,Kripke reviewed the responses of 1,004 adults to sleep ques-tionaires,in which participants indicated how much they slept during the week and whether they experienced any sleep problems. Sleep problems included waking in the middle of the night,arising early in the morning and being unable to fall back to sleep,and having fatigue interfere with day-to-day functioning.6 Kripke found that people who slept between 9 and 10 hours each night were more like-ly to report experiencing each sleep problem than people who slept 8 hours. In an interview, Kripke noted that long sleepers may struggle to get rest at night simply because they spend too much time in bed. As evidence,he added that one way to help insomnia is to spend less time in bed.“It stands to reason that if a person spends too long a time in bed,then they'll spend a higher percentage of time awake.”he said.Paragraph 5______A: Kripke's ResearchB: Dangers of Habitual Shortages of SleepC: Criticism on Kripke's ReportD: A way of Overcoming InsomniaE: Sleep Problems of Long and Short SleepersF: Classification of Sleep Problems09-21
The police crept up from behind and took the gangster by surprise.A:violent criminal B:politician C:musician D:industrialist09-24
共用题干 The Arctic Ice is ThawingFather Christmas may have to move his"workshop"from the North Pole because global warming isthawing the ice beneath his feet and his reindeers'feet as well.His"workshop"is in dire straits.The"plat- form"for the"workshop"is melting,said Stefan Norris of the World Wildlife Fund environmental group's Arctic Program.An eight-nation report by 250 scientists published recently predicted the Arctic Ocean could be ice-free in summer by 2100 because of a build-up of heat-trapping gases in the atmosphere,mainly from burning fossil fuels in cars or factories.The North Pole is getting more and more uninhabitable to Father Christmas. __________(46)Young people learn that Father Christmas'"workshop"produces millions of gifts delivered by him on a flying,reindeer-drawn sleigh.Hollywood movies like"The Polar Express"tried to make viewers believe that Father Christmas lives at the North Pole._______(47)The"Fortress of Solitude"is near the North Pole that could be under threat in a warmer world. Alan Boldt, spokesman of the Danish Ministry of Science,suggested ways to rescue Father Christmas._________(48) Another alternative,he argued,woald be building some electrical facilities to ensure the ice stays on the North Pole for him."This should be a subject for the United Nations,"he said."Danmark could build windmills to pro- vide Father Christmas with power."Denmark says Father Christmas'real home is Greenland,which will help, Denmark thinks,to strengthen its position in claiming the sovereignty over the Pole.__________(49)"Doesn't he already speak Danish?"Boldt said frostily when asked if Father Christmas would be forced to learn Danish if Denmark won international recognition of its claim to the Pole.Last month's Arctic report said the region is warming twice as fast as the rest of the globe,partly because dark ground or water,once un-covered,soaks up more heat than ice or snow.Finland has been most favored by Father Christmas and it has about 500,000 tourists a year to visit its Christmas center in Rovaniemi in Lapland._________(50)_________(49)A:However,Nordic nations all reject it by claiming that their countries are his home.B:Therefore the North Pole is the most attractive place in the world.C:If Denmark's claim were accepted internationally,it would have the legal right to search for oil and gas at the North Pole.D:One of them would be building a giant floating ice rink for the workshop if the Pole thaws.E:Maybe Father Christmas has already moved to Rovaniemi.F:He may have to move from the North Pole within our children's lifetimes. 09-21
He paused,waiting for her to digest the information.A: withholdB: exchangeC: understandD: contact09-21
共用题干 Earth's Inner CoreScientists have long struggled to understand what lies at the planet's center.Direct observation of its center is impossible,so researchers must_________(1)to other evidence.In 1889,a German scientist detected a severe earthquake in Japan.Geophysicists concluded that shock waves_________(2) jolts（晃动）from one side of Earth through the center to the other side.Then in 1936,Danish geophysicist lnge Lehmann studied the waves' __________ (3) to determine that within Earth's core of molten（熔化了的）iron lies a solid inner core一but_________(4) that core was made of eluded（难倒）her. Other geophysicists quickly determined that Lehmann's inner core was composed mostly_________(5) iron.Since then,Lehmann's discovery has _________(6) conventional Earth science.But now scientists are challenging traditional theory with new and radical_________(7).For example,Earth's center could actually contain an"inner core within the inner core."claim lshii and colleague Adam Dziewonski.Analyzing hundreds of thousands of earthquake wave _________(8),they maintain that the inner core has at its heart a tiny, even more solid sphere（球体）.This sphere"may be the oldest fossil_________(9)from the formation of Earth,"says Dziewonski.Dziewonski and Ishii speculate that shortly _________(10)Earth formed around 4.8 billion years ago,a giant asteroid（小行星）smashed into the young planet and nearly melted it.But Earth's center didn't quite melt;it_________(11)mass as the planet cooled. The core within a core may be the kernel（核心）that endured. " Its presence could change our basic ideas about the_________(12)of the planet,"Dziewonski says.Dziewonski's idea is tame（温和的）compared to the_________( 13 ) theories ofindependent geophysicist J. Marvin Herndon.Earth's inner core is made not of iron,he claims,but a_________(14)of nickel and silicon.Herndon has a truly revolutionary notion : Within the nickel silicide（硅化物）inner core is also an "inner" inner core一an 8km-wide ball of the element uranium.Uranium is radioactive.Herndon thinks the uranium releases heat energy as its atoms_________(15)fission-split and crash into one another in a chain reaction.In other words,we may live on top of a gigantic, "natural" nuclear power plant._________(10)A:after B:before C:since D:when09-21
共用题干 Wide World of RobotsEngineers who build and program robots have fascinating jobs. These researchers tinker（修补）with ma- chines in the lab and write computer software to control these devices."They're the best toys out there," says Howie Choset at Carnegie Mellon University in Pittsburgh.Choset is a roboticist,a person who designs, builds or programs robots.When Choset was a kid,he was interested in anything that moved一cars,trains,animals.He put motors on Tinkertoy cars to make them move.Later,in high school,he built mobile robots similar to small cars,Hoping to continue working on robots,he studied computer science in college.But when he got to graduate school at the California Institute of Technology in Pasadena,Choset’。labmates were working on something even cooler than remotely controlled cars:robotic snakes.Some robots can move only forward, hackward, left and right. But snakes can twist（扭曲）in many directions and travel over a lot of different types of terrain（地形）."Snakes are far more interesting than the cars,"Choset concluded.After he started working at Carnegie Mellon,Choset and his colleagues there began developing their own snake robots.Choset's team programmed robots to perform the same movements as real snakes,such as sliding and inching forward.The robot、also moved in ways that snakes usually don't,such as rolling. Choset’s snake robots could crawl（爬行）through the grass,swini in a pond and even climb a flagpole.But Choset wondered if his snakes might be useful for medicine as well.For some heart surgeries,the doctor has to open a patient's chest,cutting through the breastbone.Recovering from these surgeries can be very painful.What if the doctor could perform the operation by instead making a small hole in the body and sending in a thin robotic snake?Choset teamed up with Marco Zenati,a heart surgeon now at Harvard Medical School,to investigate theidea.Zenati practiced using the robot on a plastic model of the chest and they tested the robot in pigs. A company caikd Medrobotics in Boston is now adapting the technology for g urgerie9 on people-Even after 15 years of working with his team’s creations,"I still don't get bored of watching the motionof my robots,"Clioset says.Zenati tested the robot on people after usinlg it in pigs.A:RightB:WrongC:Not mentioned09-21
Do not waste time on insignificant points.A: interesting B: dull C: unimportant D: boring04-27
共用题干第三篇Cell Phones : Hang Up or Keep Talking?Millions of people are using cell phones today.In many places it is actually considered unusual not to use one.In many countries,cell phones are very popular with young people.They find that the phones are more than a means of communication一having a mobile phone shows that they are cool and connected.The explosions around the world in mobile phone use make some health professionals worried.Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones.In England,there has been a serious debate about this issue.Mobile phone companies are worried about the negative publicity of such ideas.They say that there is no proof that mobile phones are bad for your health.On the other hand,why do some medical studies show changes in the brain cells of some people who use mobile phones?Signs of change in the tissues of the brain and head can be detected with modern scanning （扫描）equipment. In one case , a traveling salesman had to retire at a young age because of serious memory Loss.He couldn't remember even simple tasks.He would often forget the name of his own son.This man usedto talk on his mobile phone for about six hours a day,every day of his working week,for a couple of years.His family doctor blamed his mobile phone use,but his employer's doctor didn't agree.What is it that makes mobile phones potentially harmful?The answer is radiation.High-tech machines can detect very small amounts of radiation from mobile phones.Mobile phone companies agree that there is some radiation,but they say the amount is too small to worry about.As the discussion about their safety continues,it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time.Use your mobile phone only when you really need it.Mobile phones can be very useful and convenient,especially in emergencies.In the future,mobile phones may have a warning label that says they are bad for your health.So for now,it's wise not to use your mobile phone too often.The word"detected"in Paragraph 3 could be best replaced by__________.A:curedB:removedC:discoveredD:caused09-21
共用题干 SemcoAt 21,Ricardo Semler became boss of his father's business in Brazil,Semco,which sold parts for ships. Semler Junior worked like a madman,from 7:30 a. m.until midnight every day.One afternoon,while touring a factory in New York,he collapsed.The doctor who treated him said,"There's nothing wrong with you.But if you continue like this,you'll find a new home in our hospital." Semler got the message.He changed the way he worked.In fact,he changed the way his employees worked too.He let his workers take more responsibility so that they would be the ones worrying when things went wrong. He allowed them to set their own salaries,and he cut all the jobs he thought were unnecessary,like re-- ceptionists and secretaries._______________ (46)"Everyone at Semco,even top managers,meets guests in recep- tion,does the photocopying,sends faxes,types letters and dials the phone."He completely reorganized the office:instead of walls,they have plants at Semco,so bosses can't shut themselves away from everyone else._______________ (47)As for uniforms,some people wear suits and others wear T-shirts.Semler says,"We have a sales manager named Rubin Agater who sits there reading the newspaper hour after hour. He doesn't even pretend to be busy.But when a Semco pump on the other side of the world fails and millions of gallons of oil are about to spill into the sea,Rubin springs into action.______________(48) That's when he earns his salary. No one cares if he doesn't look busy the rest of the time."Semco has flexible working hours;the employees decide when they need to arrive at work.The employees also evaluate their bosses twice a year.______________ (49)It sounds perfect,but does it work?The answer is in the numbers:in the last six years,Semco's revenues have gone from$35 million to $212 million.The company has grown from eight hundred employees to 3,000.Why?Semler says it's because of"peer pressure".Peer pressure makes employees work hard for everyone else._______________ (50)In other words,Ricardo Semler treats his workers like adults and expects them to act like adults.And they do.__________（49）A:This saved money and brought more equality to the company.B:He knows everything there is to know about our pumps and how to fix them.C:And the workers are free to decorate their workspace as they want.D:Most managers spend their time making it difficult for workers to work.E:If someone isn't doing his job well,the other workers will not allow the situation to continue.F: Also,Semco lets its workers use the company's machines for their own projects,and makes them take holidays for at least thirty days a year.09-24
共用题干第三篇Archive Gallery: The Best of Bionics（仿生学）Humans might be the most highly-evolved species on the planet,but most animals possess skills we canonly dream of having.Imagine how much electricity we could save if we could see in the dark the way cats do. Imagine leaping from tree to tree like a monkey.Giraffes（长颈鹿）,which are otherwise calm and good-natured,sleep only 4.6 hours a day.We realized a long,long time ago that nature provides the best blueprint（蓝图）for invention.We've borrowed canals from beavers（河狸）and reflectors from cat's eyes.Although the words "bionics" became popular only after the 1960s,history shows that nature has always provided ideas on solving everyday prob- lems. Our archives（档案）don't go back to the time of Leonardo da Vinci and his bird-like flying machines, but we can take you to the late 19th century,where we applied those same principles for building our firstpractical airplanes.To prepare for their flight at Kitty Hawk,the Wright brothers studied the movements of pigeons to figure out how they stayed high up when they were heavier than air. Their success inspired scores of successors to improve on the airplane by studying various aspects of nature,One of Orville Wright’、pupils caught and stuffed seagulls to examine their wingspan.Meanwhile,two French inventors examined spinning sycamore（美国梧桐）seeds in an effort to apply those same motions,reversed,to a helicopter.Some examples are more obvious than others.The outside of the airplane designed by the Wright brothers looks like a minimalistic（简单抽象艺术）structure. On the other hand , Barney Connett ' s fishsubmarine（潜水艇）actually looks like a fish.Some bio-inspired concepts have yet to be invented.In the 1960s，the US Army commissioned several university professors to conduct research on the motor skills of animals in hope of applying those same abili- ties to tanks. Tanks that run like horses or jump like grasshoppers（蚂昨）一sounds shocking,doesn't it? But imagine how life would change if we could achieve that. "Cats","monkeys"and"giraffes"mentioned in Paragraph 1 are examples to illustrate_______.A:they are highly-evolved species as humansB:animals have skills that humans do not possessC:humans can learn animals' skillsD:they are skillful in different ways09-21
共用题干 Unpopular Subjects?Is there a place in today's society for the study of useless subjects in our universities? Just over 100 years ago Fitzgerald argued in a well-written letter_______(1)Nature that"Universities must be allowed to study useless subjects一_______(2)they don't, who will?" He went on to use the_______(3) of Maxwell's electrodynamics（电动力学）as one case where a"useless subject"has been transformed to a useful subject.Nowadays this argument is again very much_______(4)in many universities. Indeed one suspects that it is one of those arguments that must be_______(5)anew （重新）by each generation. But now there is an added twist（歪曲）一subjects must not only be useful,they must also be_______(6)enough that students will flock（蜂拥） to do them,and even flock to pay to do them.As universities become commercial operations,the pressure to_______(7)subjects or departments that are less popular will become stronger and stronger. Perhapsthis is most strongly_______(8)at the moment by physics.There has been much_______(9)in the press of universities that are closing down physics departments and incorporate them with mathematics or engineering departments.Many scientists think otherwise.They see physics as a_______(10)science, which must be kept alive if only to_______(11)a base for other sciences and engineering.It is of their great personal concern that physics teaching and research is under _________(12)in many universities.How can it be preserved in the rush towards commercial competition? A major turnaround（转变）in student popularity may have to ________(13)until the industrial world discovers that it needs physicists and starts paying them well.Physics is now not only unpopular;it is also"hard".We can do more about the latterby_______（14) teaching in our schools and universities. We can also_______(15)cooperative arrangements to ensure that physicists keep their research and teaching up to date._________(4)A:powerful B:terrible C:difficult D:active04-27