历年考研英语完形填空真题（2005）The human nose is an underrated tool.Humans are often thought to be insensitive smellers compared with animals,1 this is largely because,2 animals,we stand upright.This means that our noses are 3 to perceiving those smells which float through the air,4 the majority of smells which stick to surfaces.In fact5,we are extremely sensitive to smells,6 we do not generally realize it.Our noses are capable of 7 human smells even when these are 8 to far below one part in one million.Strangely,some people find that they can smell one type of flower but not another,9 others are sensitive to the smells of both flowers.This may be because some people do not have the genes necessary to generate 10 smell receptors in the nose.These receptors are the cells which sense smells and send 11 to the brain.However,it has been found that even people insensitive to a certain smell 12 can suddenly become sensitive to it when 13 to it often enough.The explanation for insensitivity to smell seems to be that brain finds it 14 to keep all smell receptors working all the time but can 15 new receptors if necessary.This may 16 explain why we are not usually sensitive to our own smells we simply do not need to be.We are not 17 of the usual smell of our own house but we 18 new smells when we visit someone elses.The brain finds it best to keep smell receptors 19 for unfamiliar and emergency signals 20 the smell of smoke,which might indicate the danger of fire.1.Aalthough Bas Cbut Dwhile2.Aabove Bunlike Cexcluding Dbesides3.Alimited Bcommitted Cdedicated Dconfined4.Acatching Bignoring Cmissing Dtracking5.Aanyway Bthough Cinstead Dtherefore6.Aeven if Bif only Conly if Das if7.Adistinguishing Bdiscovering Cdetermining Ddetecting8.Adiluted Bdissolved Cdetermining Ddiffused9.Awhen Bsince Cfor Dwhereas10.Aunusual Bparticular Cunique Dtypical11.Asigns Bstimuli Cmessages Dimpulses12.Aat first Bat all Cat large Dat times13.Asubjected Bleft Cdrawn Dexposed14.Aineffective Bincompetent Cinefficient Dinsufficient15.Aintroduce Bsummon Ctrigger Dcreate16.Astill Balso Cotherwise Dnevertheless17.Asure Bsick Caware Dtired18.Atolerate Brepel Cneglect Dnotice19.Aavailable Breliable Cidentifiable Dsuitable20.Asimilar to Bsuch as Calong with Daside fromThe homeless make up a growing percentage of Americas population.1 homelessness has reached such proportions that local government cant possibly 2.To help homeless people 3 independence,the federal government must support job training programs,4 the minimum wage,and fund more low-cost housing.5 everyone agrees on the numbers of Americans who are homeless.Estimates 6 anywhere from 600,000 to 3 million.7 the figure may vary,analysts do agree on another matter:that the number of the homeless is 8,one of the federal governments studies 9 that the number of the homeless will reach nearly 19 million by the end of this decade.Finding ways to 10 this growing homeless population has become increasingly difficult.11 when homeless individuals manage to find a 12 that will give them three meals a day and a place to sleep at night,a good number still spend the bulk of each day 13 the street.Part of the problem is that many homeless adults are addicted to alcohol or drugs.And a significant number of the homeless have serious mental disorders.Many others,14 not addicted or mentally ill,simply lack the everyday15 skills needed to turn their lives 16.Boston Globe reporter Chris Reedy notes that the situation will improve only when there are 17 programs that address the many needs of the homeless.18 Edward Zlotkowski,director of community service at Bentley College in Massachusetts,19 it.There has to be 20 of programs.What we need is a package deal.1.AIndeed BLikewise CTherefore DFurthermore2.Astand Bcope Capprove Dretain3.Ain Bfor Cwith Dtoward4.Araise Badd Ctake Dkeep5.AGenerally BAlmost CHardly DNot6.Acover Bchange Crange Ddiffer7.ANow that BAlthough CProvided DExcept that8.Ainflating Bexpanding Cincreasing Dextending9.Apredicts Bdisplays Cproves Ddiscovers10.Aassist Btrack Csustain Ddismiss11.AHence BBut CEven DOnly12.Alodging Bshelter Cdwelling Dhouse13.Asearching Bstrolling Ccrowding Dwandering14.Awhen Bonce Cwhile Dwhereas15.Alife Bexistence Csurvival Dmaintenance16.Aaround Bover Con Dup17.Acom