填空题Just under a year ago, a sharp drop in equatorial Pacific sea-surface temperature indicated the end of the 1997~1998 E1 Nino. Called by someone "the climate event of the century", it was by several measures the strongest on record. (41)______.This is more than simply an academic question: the 1997~1998 E1 Nino severely disrupted global weather patterns and Pacific marine ecosystems, and by one estimate caused ＄033 billion in damage and cost 23,000 lives worldwide. (42)______.Clearly we have much to learn from this experience. (43)______.Now E1 Nino more generally refers to a warming of the tropical Pacific basin that occurs roughly every three to seven years in association with a weakening of the trade winds. The opposite side of El Nino, La Nina, is characterized by stronger-than-normal trade winds and unusually cold sea-surface temperatures in the tropical Pacific. Both E1 Nino and La Nina are accompanied by swings in atmospheric pressure between the eastern and western Pacific. These swings are known as the Southern Oscillation. These phenomena are collectively referred to as ENSO or E1 Nino/Southern Oscillation. The general mechanisms underlying the ENSO involve large-scale ocean-atmosphere interactions and equatorial ocean dynamics. But each El Nino and La Nina is unique in the combination of its strength, duration and pattern of development. Irregularity in the ENSO cycle can be seen both in the record dating back to the middle of the 19th century, and in other supporting data, such as lake sediments, coral growth rings and tree rings, going back hundreds or even thousands of years. (44)______. Nonetheless, the 1997~1998 E1 Nino was an unusual one. It developed so rapidly that every month between June and December 1997 set a new monthly record high for sea-surface temperatures in the eastern equatorial Pacific. Anomalies (that is, deviations from normal) in December 1997 were the highest ever recorded along the Equator in the eastern Pacific. Moreover, before 1997~ 1998, the previous record-setting E1 Nino occurred in 1982~1983. (45)______. Several factors may have contributed to the strength of the 1997~1998 E1 Nino. One is chaos, which some theories invoke to account for the irregularity of the ENSO cycle. Nonlinear resonances involving ENSO and the seasonal cycle have received special attention, but other chaotic interactions may affect ENSO as well. In 1997~1998, events possibly acted together to produce an extraordinarily strong E1 Nino simply due to the underlying tendency towards chaos in the elimate system.[A] So in principle, it should not be surprising that an unusually strong E1 Nino occurs ever so often.[B] Identifying why it was so strong challenges our understanding of the physical mechanisms responsible for E1 Nino.[C] From that perspective, the strength of the 1997~1998 E1 Nino may be but one manifestation of a linkage between interannual and decadal climate variations in the Pacific.[D] These two "super E1 Ninos" were separated by only 15 years, compared with a typical 30~40 year gap between such events earlier in the 20th century.[E] E1 Nino, Spanish for "the child" (and specifically the Christ child), is the name Peruvian fisherman gave to coastal sea-temperature warnings that first appeared around Christmas time.[F] There were warnings of a coming E1 Nino before it occurred. But although many computer forecast models predicted that 1997 would be warm in the tropical Pacific up to three seasons in advance, none predicted the rapid development or ultimate intensity of the event before it began.[G] In association with the Pacific Decadal Oscillation, sea-surface temperatures have generally been higher in the tropical Pacific from the Mid-1970s. Since then, there have been more E1 Ninos than La Ninas.

填空题C. P. Snow once said: " A sense of the future is behind all good policies. Unless we have it, we can give nothing either wise or decent to the world. " Thinking carefully about an outcome is an intelligent first step in many processes, especially when the stakes are high, possibly even dangerous. Do you have any experience in getting out of hazardous situations? In the most exceptional circumstances, a few good rules of thumb may save you. Here are five things to keep in mind. 41. Stay calm If a catastrophe threatens your life, panic will only make matters worse. Nothing but calmness can help you adequately take stock of the situation and take appropriate measures. 42. Remain confident Desperation can paralyze you or sap your energy, while confidence is the key to saving yourself. 43. Help each other You should organize for mutual assistance in case of an earthquake, flood, fire, etc. People working together can always cope more successfully with any adverse situation. Solidarity means strength; solidarity means victory. 44. Be obedient to superiors The best strategy when facing a catastrophe is to obey commands and keep order. More often than not, leaders are experts, or someone familiar with the situation or with rich experience. Being too individualistic and going your own way will usually make the situation worse for you and others. So, the best thing to do is to listen to authorities and remain orderly. 45. Communicate When in danger it is best to seek help immediately so those with more resources can come to your aid. If you are at risk, use whatever means available as soon as possible to contact others for help, and take efforts to maintain communication once it is established. While every catastrophe is different in its own way, all can be met and hopefully overcome with the above-mentioned pieces of advice. By carefully considering what needs to be done, even under the worst of situations, one can find solutions, or endure until aided by others.[A] A person trapped in ruins in an earthquake, didn't lose hope. The victim overcame his pain and despair, and kept banging out signals on the fallen wall around him for help. Because of his efforts, a rescue team was able to find him and save his life.[B] For example, if numerous people are involved in a dangerous situation, some, out of fear or inclination, may not follow direction or heed sound advice. As a result of the disorder, rescue efforts are hindered, or worse more casualties are incurred.[C] Nine fishermen from Peru were hit by a severe storm, but they didn't panic even though their boat was damaged so badly that they couldn't sail home. They maintained faith that they would surely to be saved, and their belief gave them strength. When there is hope, there is a way! They survived at sea for 40 days before they were finally rescued. Their story is a good sample for future people lost at sea. It is best to remember the proverb: God helps those who help themselves.[D] History shows that when people are in danger mutual assistance promotes confidence, and reassuring others not only helps them, but can calm you as well. Helping others is beneficial, especially in the direst circumstances. During the Sept. 11 attacks in America, people pulled together and supported each other. This not only reduced casualties, but also left a deep impression on people around world. Remember, helping others is helping yourself![E] The Apollo 13 space mission suffered catastrophic mechanical problems en route to the Moon. Its malfunction was caused by an explosion and rupture of oxygen tank No. 2 in the service module. The NASA Mission Control Center immediately issued two orders. The second order was concerning navigation. But, can you guess what the first order was? Unbelievably, the astronauts were told to take two tranquillizer pills each! As a result, calmness helped the astronauts overcome a series of difficulties and return to earth. Calmness can work miracles in times of emergency.[F] The best way to prevent a catastrophe from happening is planning ahead. You should often check your circuits, stoves, electrical appliances and gas pipelines. Before sleeping in a hotel, you should be aware of the nearest exit in case of an emergency. " Preparation avers peril. "

填空题{{B}}Directions:{{/B}}Thefollowingparagraphsaregiveninawrongorder.ForQuestions41-45,youarerequiredtoreorganizetheseparagraphsintoacoherenttextbychoosingfromthelistA-Gtofillineachnumberedbox.ThefirstandthelastparagraphshavebeenplacedforyouinBoxes.MarkyouranswersonANSWERSHEET1.[A]ThestrainofHIVthatwasdiscoveredinSydneyintriguesscientistsbecauseitcontainsstrikingabnormalitiesinagenethatisbelievedtostimulateviralduplication.Infact,thevirusismissingsomuchofthisparticulargene-knownasnef,fornegativefactor--thatitishardtoimaginehowthegenecouldperformanyusefulfunction.Andsureenough,whiletheSydneyvirusretainstheabilitytoinfectTcells--whitebloodcellsthatarecriticaltotheimmunesystem'sabilitytowardoffinfection--itmakessofewcopiesofitselfthatthemostpowerfulmoleculartoolscanbarelydetectitspresence.[B]Ifthisspeculationprovesright,itwillmarkamilestoneinthebattletocontainthelate-20thcentury'smostterribleepidemic.ForinadditiontoexplainingwhythissmallgroupofpeopleinfectedwithHIVhasnotbecomesick,thediscoveryofaviralstrainthatworkslikeavaccinewouldhavefar-reachingimplications."Whattheseresultssuggest,"saysDr.BarneyGrahamofTennessee'sVanderbiltUniversity,"isthatHIVisvulnerableandthatitispossibletostimulateeffectiveimmunityagainstit."[C]Butassixyearsstretchedto10,thento14,theanxietyofhealthofficialsgavewaytoastonishment.Althoughtwooftherecipientshavediedfromothercauses,notoneoftheman'scontaminatedbloodhascomedownwithAIDS.Moretellingstill,thedonorisalsohealthy.InfacthisimmunesystemremainsasrobustasifhehadnevertangledwithHIVatall.Whatcouldexplainsuchunexpectedgoodfortune?[D]Attheveryleast,thenefgeneoffersanattractivetargetfordrugdevelopers.Ifitsactivitycanbeblocked,suggestsDeacon,researchersmightbeabletobringtheprogressionofdiseaseundercontrol,eveninpeoplewhohavedevelopedfull-blownAIDS.TheneedforbetterAIDS-fightingdrugswasunderscoredlastweekbytheactionsofaU.S.FoodandDrugAdministrationadvisorypanel,which,recommendedspeedyapprovaloftwonewAIDSdrugs.AlthoughFDAcommissionerDavidKesslerwasquicktopraisethenewdrugs,neithermedicationcanpreventorcureAIDSonceithastakenhold.Whatscientistsreallywantisavaccinethatcanpreventinfectionaltogether.Andthat'swhatmakestheSydneyvirussopromising--andsocontroversial.[E]AteamofAustralianscientistshasfinallysolvedthemystery.Thevirusthatthedonorcontractedandthenpassedon,theteamreportedlastweekinthejournalScience,containsflawsinitsgeneticscriptthatappeartohaverendereditharmless."Notonlyhavetherecipientsandthedonornotprogressedtodiseasefor15years,"marvelsmolecularbiologistNicholasDeaconofAustralia'sMacfarlaneBurnetCentreforMedicalResearch,"butthepredictionisthattheyneverwill."Deaconspeculatesthatthis"impotent"HIVmayevenbeanaturalinoculantthatprotectsitscarriersagainstmorevirulentstrainsofthevirus.[F]ButfewscientistsareenthusiasticabouttestingthepropositionbyinjectingHIV--howeverweakened--intomillionsofpeoplewhohaveneverbeeninfected.Afterall,theynote,HIVisaretrovirus,aclassofinfectiousagentsknownfortheiralarmingabilitytointegratetheirowngenesintotheDNAofthecellstheyinfect.Thusonceittakeseffect,aretrovirusinfectionispermanent.[G]About15yearsago,awell-meaningmandonatedbloodtotheRedCrossinSydney,Australia,notknowinghehasbeenexposedtoHIV-1,thevirusthatcausesAIDS.Muchlater,publichealthofficialslearnedthatsomeofthepeoplewhogottransfusionscontaininghisbloodhadbecomeinfectedwiththesamevirus;presumablytheywerealmostsuretodie.Order:

填空题41. Two types of stress: There are basically two types of stress placed on human beings--physical and mental. 42. Effects of stress--physical or emotional: Whether physical or emotional in origin, stress causes the body to react in the same way. 43. Guilty--useful, though most harmful: Probably the most harmful of all the stresses is guilt. 44. Instances no need to feel guilty: However, many of us as children learned rules that we no longer need. No one is perfect: Guilt and the worry that often accompanies this major stress are difficult to eradicate, but people subject to excessive guilt feelings should realize, as simple as it sounds, that no one is perfect. People cannot always be cheerful and helpful to every one they meet. Another good lesson is that mistakes should be forgotten, not lingered over and brought out to examine periodically. 45. Life with a little stress--significant: A life without stress, such as retirement with nothing to do, would be boring.[A] Fat adults should no longer feel guilty about leaving a little food on the plate, a successful businessman need not feel guilty about spending a little too much money on a vacation, nor should he feel guilty that he can combine a business trip to the West Coast with some swimming and golf at an ocean resort. But many people do feel guilty over such apparently innocent actions. Excessive guilt can sour all of life and make life not worth living; it can also cause self-hatred as well as other fears and anxieties that cause all life's successes to be bittersweet, at best.[B] Stress from physical activity, if not carried too far, is actually beneficial. Exercise relaxes you and may help forget about mental and emotional stress. But mental stress is almost always bad for you. If mental stress is unrelieved, it can actually cause diseases such as ulcers, migraine headaches, heart problems, or mental illness.[C] Just as we need a little guilt--to keep us correct and a little worry--to make us plan ahead--we need a little stress to stay interested in life. But when stress begins to bother you, you might as well change your routine. Take your mind off your worries with some physical activity; you may discover a solution you have overlooked before.[D] Stress is a natural part of everyday life and there is no way to avoid it. In fact, it is not the bad thing it is often supposed to be. A certain amount of stress is vital to provide motivation and give purpose to life. It is only when the stress gets out of control that it can lead to poor performance and ill health.[E] Some people are not afraid of stress, and such characters are obviously prime material for managerial responsibilities, others lose heart at the first signs of unusual difficulties.[F] In the first stage, your body prepares to meet the stress. The heartbeat and respiration rates increase, and the pupils of the eyes dilate; the blood sugar level increases, and the rate of perspiration speeds up, while digestion slows down as blood and muscular activity is diverted elsewhere. In the second stage, your body returns to normal and repairs any damage caused by the stressful situation. However, if stress continues, the body cannot repair itself, and the final stage, exhaustion, then begins. If this stage continues, if for example you are frustrated by your work and continue to be frustrated for a long time, physical or emotional damage will occur. These stages of stress reaction are always the same, whether the stress is caused by a cross-country run, a first date, buying a house, or narrowly missing an automobile accident.[G] This common emotion is useful to have when it helps us to realize that we have, in fact, committed some error, violated our own rules or social rules. If we did not feel guilty, we would never do anything except the things that brought us immediate pleasure-- we'd never obey the law, work, exercise, or even study in school, unless we wanted to do so in the first place. As a person's conscience develops, guilt feelings become inevitable; guilt is the sorrow we experience when we know we have done something incorrect.

填空题 [A] What route does HIV take after it enters the body to destroy the immune system?[B] How and when did the long-standing belief concerning AIDS and HIV crop up?[C] What is the most effective anti-HIV therapy?[D] How does HIV subvert the immune system?[E] In the absence of a vaccine, how can HIV be stopped?[F] Why does AIDS predispose infected persons to certain types of cancer and infections? In the 20 years since the first cases of AIDS were detected, scientists say they have learned more about this viral disease than any other. Yet Peter Piot, who directs the United Nations AIDS program, and Stefano Vella of Rome, president of the International AIDS Society, and other experts say reviewing unanswered questions could prove useful as a measure of progress for AIDS and other diseases. Among the important broader scientific questions that remain:41．_____________. A long-standing belief is that cancer cells constantly develop and are held in check by a healthy immune system. But AIDS has challenged that belief. People with AIDS are much more prone to certain cancers like non-Hodgkins lymphomas and Kaposi's sarcoms, but not to breast, colon and lung, the most common cancers in the United States. This pattern suggests that an impaired immune system, at least the type that occurs in AIDS, does not allow common cancers to develop.42．_______________. When HIV is transmitted sexually, the virus must cross a tissue barrier to enter the body. How that happens is still unclear. The virus might invade directly or be carried by a series of different kinds of cells. Eventually HIV travels through lymph vessels to lymph nodes and the rest of the lymph system. But what is not known is how the virus proceeds to destroy the body's CD-4 cells that are needed to combat invading infectious agents.43．_______________. Although HIV kills the immune ceils sent to kill the virus, there is widespread variation in the rate at which HIV infected people become ill with AIDS. So scientists ask: Can the elements of the immune system responsible for that variability be identified? If so, can they be used to stop progression to AIDS in infected individuals and possibly prevent infection in the first place?44．_______________. In theory, early treatment should offer the best chance of preserving immune function. But the new drugs do not completely eliminate HIV from the body so the medicines, which can have dangerous side effects, will have to be taken for a lifetime and perhaps changed to combat resistance. The new policy is expected to recommend that treatment be deferred until there are signs the immune system is weakening.{{B}} Is a vaccine possible?{{/B}} There is little question that an effective vaccine is crucial to controlling the epidemic. Yet only one has reached the stage of full testing, and there is wide controversy over the degree of protection it will provide. HIV strains that are transmitted in various areas of the world differ genetically. It is not known whether a vaccine derived from one type of HIV will confer protection against other types.45．_______________. Without more incisive, focused behavioral research, prevention messages alone will not put an end to the global epidemic.

填空题{{B}}Directions:{{/B}} You are going to read a list of headings and a text about the development of maritime laws. Choose the most suitable heading from the list A-F for each numbered paragraph (41-45). The first and last paragraphs of the text are not numbered. There is one extra heading which you do not need to use. Mark your answers on ANSWER SHEET 1. [A] Fist convention of Comite Maritime International[B] The convention having been revised three times[C] Why is unification of maritime law necessary?[D] The convention with the most signature states.[E] Incompatible time scale[F] The salvage convention According to Constitution: "The Comite Maritime International (CMI) is a non-governmental international organization, the object of which is to contribute by all appropriate means and activities to the unification of maritime law in all its aspects. To this end it shall promote the establishment of national associations of maritime law and shall co-operate with other international organizations. "The CMI has been doing just that since 1897.41______ In an address to the University of Turin in 1860, the Jurist Mancini said: "The sea with its winds, its storms and its dangers never changes and this demands a necessary uniformity of juridical regime." In other words, those involved in the world of maritime trade need to know that wherever they trade the applicable law will, by and large, be the same. Traditionally, uniformity is achieved by means of international conventions or other forms of agreement negotiated between governments and enforced domestically by those same governments.42______ It is tempting to measure the success of a convention on a strictly numerical basis. If that is the proper criterion of success, one could say that one of the most successful conventions ever produced was the very first CMI convention--the Collision Convention of 1910. The terms of this convention were agreed on September 23, 1910 and the convention entered into force less than three years later, on March 1, 1913.43______ Almost as successful, in numerical terms, is a convention of similar vintage, namely the Salvage Convention of 1910. Less than three years elapsed between agreement of the text at the Brussels Diplomatic Conference and entry into force on March 1, 1913. we are, quite properly, starting to see a number of denunciations of this convention, as countries adopt the new salvage Convention of 1989. It is worth recording that the Salvage Convention of 1989, designed to replace the 1910 Convention, did not enter into force until July 1996, more than seven years after agreement. The latest information available is that forty States have now ratified or acceded to the 1989 convention.44______ The text of the first Limitation Convention was agreed at the Brussels Diplomatic Conference in August 1924, but did not enter into force until 1931-seven years after the text had been agreed. This convention was not widely supported, and eventually attracted only fifteen ratifications or accessions. The CMI had a second go at limitation with its 1957 Convention, the text of which was agreed in October of that year. It entered into force in May 1968 and has been ratified or acceded to by fifty-one states, though of course a number have subsequently denounced this convention in order to embrace the third CMI Limitation Convention, that of 1976. At the latest count the 76 Convention has been ratified or acceded to by thirtyseven states. The fourth instrument on limitation, namely the 1996 Protocol, has not yet come into force, despite the passage of six years since the Diplomatic Conference at Which the text of the was agreed.45______ By almost any standard of measurement, the most successful maritime law convention of all time: the Civil Liability Convention of 1969. The text of that convention ( to which the CMI contributed both in background research and drafting) was agreed at a Diplomatic Conference in 1969 and it entered into force six years later, in June 1975. The convention has, at various stages, been acceded to or ratified by 103 states (with two additional "provisional" ratifications). If we add to this the various states and dependencies that come in under the UK umbrella, we realize that we are looking at a hugely successful convention. Conventions and other unifying instruments are born in adversity. An area of law may come under review because one or two' states have been confronted by a maritime legal problem that has affected them directly. Those sponsoring states may well spend some time reviewing the problem and producing the first draft of an instrument. Eventually, this draft may be offered to the International Maritime Organisation' s ( IMO ) Legal Committee for inclusion in its work program. Over ensuing years (the Legal Committee meeting every sic months or so), issues presented by the draft will be debated, new issues will be raised, and the instrument will be endlessly re-drafted. At some stage, the view will be taken that the instrument is sufficiently mature to warrant a Diplomatic Conference at which the text will be finalized. If the instrument is approved at the Diplomatic Conference, it will sit for twelve monthsawaiting signature and then be open to ratification and accession. The instrument will contain an entry into force requirement, which will need to be satisfied.

填空题Industrial safety does not just happen

填空题All big ideas start life on the fringes of debate. Very often it takes a shocking event to move them into the mainstream. Unti1 last year climate change was mainly the interest of scientists and green lobbyists. But since Hurricane Katrina, something seems to have changed, particularly in America. Nobody knows whether the hurricane really had anything to do with the earth warming. But for the first time less green voters and big business had a clearer idea about the "extreme weather events" whose increasing frequency scientists had been talking about. There are plenty of anecdotal signs of change: Britain's pro-business Conservatives have turned green; A1 Gore is back in fashion in America; hybrid cars no longer get stared at. (41)______. So far the political rows about global warming have centred on two polluters, smoggy factories and dirty cars. (42)______. In some ways, the airlines are an odd target for greens. They produce only around 3% of the world's man-made carbon emissions. (43)______. By shipping hordes of ordinary people around the globe for not very much money, they have improved the lives of millions. (44)______. Air transport will soon be central, not marginal, to the emissions issue. What, if anything, should be done? As usual, there are dangers on both sides. Excessive regulation would unnecessarily restrict individual choice and restrain an industry that makes both rich and poor countries better off. On the other hand, airlines no less than any other industry must pay for pollution. (45)______. And, although other forms of transport cannot easily replace flying, demand for many flights is sensitive to price. A quarter of flying is business-related; many of those journeys are essential, but others are scarcely more important than a telephone call or video-conference. However, addressing individuals' consciences won't go that far. Air pollution is a collective problem, which in this case requires a change in policy. As it stands, the market is in favour of air travel; the aim should be to make it more balanced. Two approaches are on offer. Some think the best way to limit emissions is to tax them; others argue for a system that sets a cap on pollution, and let polluters trade the right to emit.[A] But there is no sign of governments embracing that idea. Given that it is the world's first serious attempt to cut emissions internationally, that is not surprising. The world can learn from its imperfections, and design a better scheme for airlines.[B] Now a new front is being opened up—in the skies. Next month the European Parliament will vote on whether to extend its emissions-trading system to airlines. If it decides in favour, the whole industry will feel the impact, for it will affect not just European airlines but all those that fly into and out of the EU. But whatever happens in the EU, it seems that the airlines are bound to face demands that they should pay for their emissions.[C] Slowly, businessmen and politicians are coming to agree with scientists. If this generation does not tackle climate change, its descendants will not think much of it. That means raising costs for all sources of pollution. Even those inexpensive weekend breaks will be cancelled.[D] As the debate grows, some flyers may reconsider their ways. Put frankly, air travel makes a mockery of many people's attempts to live a green life. Somebody who wants to reduce his "carbon footprint" can bicycle to work, never buy sprays and turn off his air-conditioner—and still blow away all this virtue on a couple of long flights.[E] Companies are beginning to take actions and encouraging governments to do the same. Europe already has an emissions-trading system (ETS) for its five dirtiest industries. In America, although the Bush administration still resists federal legislation, more and more states do not.[F] Yet in other ways, airlines are a fine target. They pay no tax on fuel for international flights, and therefore escape the "polluter pays" principle. Their emissions are especially damaging, too, And the industry's energy consumption has been growing faster than that of other polluting industries.[G] Surface transport, by contrast, produces 22%. Europe's merchant ships spew out around a third more carbon than aircraft do, and nobody is going after them. And unlike cars— potent symbols of individualism (and, some would say, individual selfishness) — airlines are public transport, jamming in as many people as they can into each plane.

填空题[A]Forexample,theUnitedStatesisamajorconsumerofcoffee,yetitdoesnothavetheclimatetogrowanyofitsown.Consequently,theUnitedStatesmustimportcoffeefromcountries(suchasBrazil,ColombiaandGuatemala)thatgrowcoffeeefficiently.Ontheotherhand,theUnitedStateshaslargeindustrialplantscapableofproducingavarietyofgoods,suchaschemicalsandairplanes,whichcanbesoldtonationsthatneedthem.Ifnationstradeditemforitem,suchasoneautomobilefor10,000bagsofcoffee,foreigntradewouldbeextremelycumbersomeandrestrictive.Soinsteadofbarter,whichisthetradeofgoodswithoutanexchangeofmoney,theUnitedStatesreceivesmoneyinpaymentforwhatitsells.ItpaysforBraziliancoffeewithdollars,whichBrazilcanthenusetobuywoolfromAustralia,whichinturncanbuytextilesfromGreatBritain,whichcanthenbuytobaccofromtheUnitedStates.[B]Foreigntradealsooccursbecauseacountryoftendoesnothaveenoughofaparticularitemtomeetitsneeds.AlthoughtheUnitedStatesisamajorproducerofsugar,itconsumesmorethanitcanproduceinternallyandthusmustimportsugar.[C]Foreigntrade,theexchangeofgoodsbetweennations,takesplaceformanyreasons.Thefirst,asmentionedaboveisthatnonationhasallofthecommoditiesthatitneeds.Rawmaterialsarescatteredaroundtheworld.LargedepositsofcopperareminedinPeruandZaire,diamondsareminedinSouthAfricaandpetroleumisrecoveredintheMiddleEast.Countriesthatdonothavetheseresourceswithintheirownboundariesmustbuyfromcountriesthatexportthem.[D]Intoday'scomplexeconomicworld,neitherindividualsnornationsareself-suffi-cient.Nationshaveutilizeddifferenteconomicresources;peoplehavedevelopeddifferentskills.Thisisthefoundationofworldtradeandeconomicactivity.Asaresultofthistradeandactivity,internationalfinanceandbankinghaveevolved.[E]Finally,foreigntradetakesplacebecauseofinnovationorstyle.EventhoughtheUnitedStatesproducesmoreautomobilesthananyothercountry,itstillimportslargenumbersofautosfromGermany,JapanandSweden,primarilybecausethereisamarketforthemintheUnitedStates.[F]Formostnations,exportsandimportsarethemostimportantinternationalactivity.Whennationsexportmorethantheyimport,theyaresaidtohaveafavorablebalanceoftrade.Whentheyimportmorethantheyexport,anunfavorablebalanceoftradeexists.Nationstrytomaintainafavorablebalanceoftrade,whichassuresthemofthemeanstobuynecessaryimports.[G]Third,onenationcansellsomeitemsatalowercostthanothercountries.Japanhasbeenabletoexportlargequantitiesofradiosandtelevisionsetsbecauseitcanproducethemmoreefficientlythanothercountries.ItischeaperfortheUnitedStatestobuythesefromJapanthantoproducethemdomestically.Accordingtoeconomictheory,Japanshouldproduceandexportthoseitemsfromwhichitderivesacomparativeadvantage.Itshouldalsobuyandimportwhatitneedsfromthosecountriesthathaveacomparativeadvantageinthedesireditems.Order:

填空题 Every now and then a study comes along whose chief interest lies in how peculiarly askew its findings seem to be from the common perception of things. Sometimes, of course, the "surprising new study" itself turns out to be off in some way. But if the data are fundamentally sound, then what you really want to know is why sensible people hold such a contrary view. 41___________________. Researchers took a closer look at an earlier study that had been widely interpreted, when it was first published in 2000, as proof that the homework monster was growing, and insatiable. A Time magazine cover article spawned a minigenre of trend stories, all peopled by pale, exhausted kids and bewildered boomer parents whose own homework memories seemed to encompass only felt puppets and shoe-box dioramas. But the new report points out that while the amount of time schoolchildren 12 and under devoted to study at home did indeed grow between 1981 and 1997, the increase was small: an average of 23 minutes per week. 42___________________. So why do so many parents seem to think otherwise? One answer is that the real increase in homework that has been documented is among younger children. In 1981, for instance, one-third of 6- to 8-year-olds had some homework; one-half did in the late 90's. 43___________________. Since children 6 to 8 are the ones we particularly like to think of as engaged in unstructured play--we imagine them riding bikes in the honeyed light of waning afternoons, even when what they might well be doing, in the absence of homework, is watching TV-homework for them seems like one of those heavy-handed incursions on the freedom of childhood. 44___________________. These children go to elite private schools or to demanding public ones where the competitive pressures are such that they either really do have hours of homework each night or take hours finishing it because they (or their parents) are so anxious that it be done well. They come from the demographic that makes a cultural, almost a. moral, ideal of enrolling children in soccer and oboe lessons and karate and ballet, and so their time really is at a premium. 45___________________. A. Moreover, 20 percent fewer children between the ages of 9 and 12 were doing homework at all in 1997 than in 1981. And high-school students spent no more time on homework than they did in previous decades. B. That is certainly the question raised by a Brookings Institution report released last month showing that the amount of time kids devote to homework has not, in fact, significantly increased over the last two decades. C. Behind the seeming contradictions of steady homework levels and the anti-homework backlash, in other words, is the reality of social class. D. They are likely to have busy professional parents, oversubscribed themselves but with an investment in seeing their children produce book reports of a kind that teachers, counselors and, in time, college admissions boards will find impressive. E. Anti-homework crusades are not new-in 1901, for example, California passed a law abolishing homework for grades one through eight-but they have usually been led by the same kinds of people, which is to say, elites. F. Since parents are more likely to have to supervise a first or second grader doing homework than an older child, the earlier launching of a homework regimen might feel like a disproportionate increase in the parental workload. G. But the bigger answer, I suspect, is that the parents we tend to hear from in the press, at school-board meetings and in Internet chat groups, the parents with elaborated, developmentally savvy critiques of standards and curriculums, are parents whose children really are experiencing a time crunch.

填空题Most people would not object to living a few years longer than normal, as long as it meant they could live those years in good health. Sadly, the only proven way to extend the lifespan of an animal in this way is to reduce its calorie intake. Studies going back to the 1930s have shown that a considerable reduction in consumption ( about 50% ) can extend the lifespan of everything from dogs to nematode worms by between 30% and 70%. Although humans are neither dogs nor worms, a few people are willing to give the calorie-restricted diet a try in the hope that it might work for them, too. But not many--as the old joke has it, give up the things you enjoy and you may not live longer, but it will sure seem as if you did. Now, though, work done by Marc Hellerstein and his colleagues at the University of California, Berkeley, suggests that it may be possible to have, as it were, your cake and eat it too. Or, at least, to eat 95% of it. Their study, to be published in the American Journal of Physiology--Endocrinology and Metabolism, suggests that significant gains in longevity might be made by a mere 5% reduction in calorie intake. The study was done on mice rather than people. But the ubiquity of previous calorie-restriction results suggests the same outcome might well occur in other species, possibly including humans. However, you would have to fast on alternate days. (41) ______ Cancer is the uncontrolled growth of cells. For a cancer to develop efficiently, it needs multiple mutations to accumulate in the DNA of the cell that becomes the tumor's ancestor. (42) ______ A slower rate of cell division thus results in a slower accumulation of cancer-causing mutations. (43) ______ Heavy water is heavy because the hydrogen in it weighs twice as much as ordinary hydrogen (it has a proton and a neutron in its nucleus, instead of just a proton). Chemically, however, it behaves like its lighter relative. This means, among other things, that it gets incorporated into DNA as that molecule doubles in quantity during cell division. (44) ______ Dr Hellerstein first established how much mice eat if allowed to feed as much as they want. Then he set up a group of mice that were allowed to eat only 95% of that amount. In both cases, he used the heavy-water method to monitor cell division. The upshot was that the rate of division in the calorie-restricted mice was 37% lower than that in those mice that could eat as much as they wanted--which could have a significant effect on the accumulation of cancer-causing mutations. (45) ______[A] To stop this happening, cells have DNA-repair mechanisms. But if a cell divides before the damage is repaired, the chance of a successful repair is significantly reduced.[B] Bingeing and starving is how many animals tend to feed in the wild. The uncertain food supply means they regularly go through cycles of too much and too little food ( it also means that they are often restricted to eating less than they could manage if food were omnipresent).[C] But calorie-reduction is not all the mice had to endure. They were, in addition, fed only on alternate days: bingeing one day and starving the next. So, whether modern man and woman, constantly surrounded by food and advertisements for food, would really be able to forgo eating every other day is debatable.[D] Why caloric restriction extends the lifespan of any animal is unclear, but much of the smart money backs the idea that it slows down cell division by denying cells the resources they need to grow and proliferate. One consequence of that slow-down would be to hamper the development of cancerous tumors.[E] So, by putting heavy water in the diets of their mice, the researchers were able to measure how much DNA in the tissues of those animals had been made since the start of the experiment (and by inference how much cell division had taken place), by the simple expedient of extracting the DNA and weighing it.[F] The second reason, according to Elaine Hsieh, one of Dr Hellerstein's colleagues, is that cutting just a few calories overall, but feeding intermittently, may be a more feasible eating pattern for some people to maintain than making small reductions each and every day.[G] At least, that is the theory. Until now, though, no one has tested whether reduced calorie intake actually does result in slower cell division. Dr Hellerstein and his team were able to do so using heavy water as a chemical "marker" of the process.

填空题{{B}}Directions:{{/B}}You are going to read a list of headings and a text about happiness. Choose the most suitableheading from the list A-- F for each numbered paragraph (41--45). The first and last paragraphs of the text are not numbered. There is one extra heading which you do not need to use. Mark your answers on ANSWER SHEET 1. [A] Extensive applications of haptic technology.[B] Possibilities rendered by haptic mechanisms.[C] The feasibility of extending our senses and exploring abstract universes.[D] An example of the progress in science of haptics.[E] Bringing the potential of our senses into full play.[F] Will haptics step into a bright future? "OOOF!" Using your mouse, you heave a data file across the screen--a couple of gigabytes of data weigh a lot. Its rough surface tells you that it is a graphics file. Having tipped this huge pile of data into a hopper that sends it to the right program, you examine a screen image of the forest trail you'll be hiking on your Vacation. Then, using a gloved hand, you master its details by running your fingers over its forks and bends, its sharp rises and falls. Later you send an E-mail to your beloved, bending to the deskpad to attach a kiss. 41．______________ The science of haptics (from the Greek haptesthai, "to touch") is making these fantasies real. A few primitive devices are extending human-machine communication beyond vision and sound. Haptic joysticks and steering wheels for computer games are already giving happy players some of the sensations of piloting a spaceship, driving a racing car or firing weapons. In time, haptic interfaces may allow us to manipulate single molecules, feel clouds and galaxies, even reach into higher dimensions to grasp the subtle structures of mathematics. 42．______________ Most of our senses are passive. In hearing and vision, for example, the sound or light is simply received and analyzed. But touch is different: we actively explore and alter reality with our hands, so the same action that gathers information can also change the world--to model a piece of clay or press a button, for example. In providing direct contact between people, touch carries emotional impact. And in providing direct contact with the world, it is the sure sign of reality, as in "pinch me--am I dreaming?" 43．______________ Some small steps have even been taken towards whole-body haptics. Touch Technology of Nova Scotia, Canada, has built a haptic chair. It looks like a full length lounge chair in a family den, but its surface is studded with 72 "tactors" -pneumatic piston rods, covered with rounded buttons, that can extend about an inch, and can be driven under computer control in any desired sequence and pattern. It could be programmed to imitate a real massage or to function in time to music. According to the manufacturer, that provides a powerful blending of sen-sations--a long term goal of virtual reality. 44．______________ Even at its present crude level, however, haptics can make tangible what once could not be touched or even pictured. To investigate the world of the very small, researchers at the University of North Carolina, Chapel Hill, have developed the nanoManipulator. This adds touch to the technique of scanning probe microscopy, which can image a single atom by monitoring either the electrical current flowing between an extremely fine probe and a surface or the force between them. With the nanoManipulator, researchers can see and manipulate a universe a million times smaller than their own, to study viruses and tiny semiconducting devices. If the force feedback can be made sensitive enough, it may be possible to push molecular keys into specific molecular locks, to custom-design drugs or assemble silicon parts into intricate nanomachines. With other interfaces, there is no reason we shouldn't also be able to touch the very large-clouds, ocean currents, mantle flows, mountains, galaxy clusters. Or the very strong--with a suitable force scaling, new ceramics or alloys could be squeezed and twanged to test their engineering properties. Or the physically extreme and inaccessible--such as ultra hot plasma flows in fusion machines. 45．______________ Haptic technology could even make abstract ideas tangible. Many scientific concepts occupy spaces of more than three dimensions: string theory, for example, asserts that we live in a 10 or 11-dimensional Universe. As it is impossible to visualise such a space, we explore these ideas through mathematical expressions or two dimensional sketches on paper, But probing these unfamiliar geometries with touch may be more effective. And for blind people, haptics offers a new way to grasp information even in three dimensions. A group at the University of Delaware has developed an environment where a person can feel a mathematical function. Using a PHAN-TOM, the user "walks" along the surface of the figure. Like a hiker following mountainous terrain, the user feels where the function is steep, where it is level, and where its peaks and valleys lie. Other haptic systems could help blind people to browse the Internet, feeling images as well as words. The future of haptics is bright, but the only sensual relationship it will be sustaining any time soon is between you and your computer.

填空题A."Itisalwaysbettertobuyahouse;payingrentislikepouringmoneydownthedrain."Foryears,suchadvicehasencouragedpeopletoborrowheavilytogetonthepropertyladderassoonaspossible.Butisitstillsoundadvice?Housepricesarecurrentlyatrecordlevelsinrelationtorentsinmanypartsoftheworldanditnowoftenmakesmorefinancialsense—especiallyforfirst-timebuyers—torentinstead.B."IfIdon'tbuynow,I'llnevergetonthepropertyladder"isacommoncryfromfirst-timebuyers.Ifhousepricescontinuetooutpacewages,thatistrue.Butitnowlooksunlikely.Whenpricesgetoutoflinewithwhatfirst-timerscanafford,astheyaretoday,theyalwayseventuallyfallinrealterms.Themyththatbuyingisalwaysbetterthanrentinggrewoutofthehighinflationeraofthe1970sand1950s.First-timebuyersthenalwaysendedupbetteroffthanrenters,becauseinflationerodedtherealvalueofmortgagesevenwhileitpusheduprents.Mortgage-interesttaxreliefwasalsoworthmorewheninflation,andhencenominalinterestrates,washigh.Withinflationnowtamed,homeownershipisfarlessattractive.C.Homebuyerstendtounderestimatetheircosts.Oncemaintenancecosts,insuranceandpropertytaxesareaddedtomortgagepayments,totalannualoutgoingsnoweasilyexceedthecostofrentinganequivalentproperty,evenaftertakingaccountoftaxbreaks.Ah,butcapitalgainswillmorethanmakeupforthat,itispopularlyargued.Overthepastsevenyears,averagehousepricesinAmericahaverisenby65%,thoseinBritain,Spain,AustraliaandIrelandhavemorethandoubled.Butitisunrealistictoexpectsuchgainstocontinue.Makingthe(optimistic)assumptionthathousepricesinsteadriseinlinewithinflation,andincludingbuyingandsellingcosts,thenoveraperiodofsevenyears,—theaveragetimeAmericanownersstayinonehouse—ourcalculationsshowthatyouwouldgenerallybebetteroffrenting.D.Bewarned,ifyoumakesuchaboldclaimatadinnerparty,youwillimmediatelybesetupon.Payingrentisthrowingmoneyaway,itwillbeargued.Muchbettertospendthemoneyonamortgage,andbysodoingbuildupequity.Thesnagisthatthetypicalfirst-timebuyerkeepsahouseforlessthanfiveyears,andduringthattimemostmortgagepaymentsgooninterest,notonrepayingtheloan.Andifpricesfall,itcouldwipeoutyourequity.E.Inanycase,arentercanaccumulatewealthbyputtingthemoneysavedeachyearfromthelowercostofrentingintoshares.Thesehave,historically,yieldedahigherreturnthanhousing.Puttingallyourmoneyintoahousealsobreaksthebasicruleofprudentinvesting:diversify.Andyes,itistruethatamortgageleveragesthegainsonyourinitialdepositonahouse,butitalsoamplifiesyourlossesifhousepricesfall.F.Thedivergencebetweenrentsandhousepricesis,ofcourse,evidenceofahousingbubble.Somedaypriceswillfallrelativetorentsandwages.Aftertheydo,itwillmakesensetobuyahome.Untiltheydo,thesmartmoneyisonrenting.G."Iwanttohaveaplacetocallhome"isapopularretort.Rentingprovideslesslong-termsecurityandyoucannotpaintallthewallsorangeifyouwantto.Homeownershipisanexcellentpersonalgoal,butitmaynotalwaysmakefinancialsense.Theprideof"owning"yourownhomemayquicklyfadeifyouaresaddledwithamortgagethatcostsmuchmorethanrenting.Also,rentingdoeshavesomeadvantages.Rentersfinditeasiertomoveforjoborfamilyreasons.{{B}}Order:{{/B}}