大学英语英语四级练习卷及答案 (五)

大学英语四级考试

练习卷

一、阅读理解

Passage1

Rainmaking

Theideaofrainmakingisalmostasoldasman,butitwasnotuntil1946

thatmansucceededinmakingrain.Inancienttimes,rainmakershadclaimed

tobringrainbymanymethods:dancing,singing,killingvariouskinds

oflivingcreatures(includinghumans),andblowingastreamofwater

intotheairfromakindofpipe.

Morerecently,somerainmakersclaimedtomakerainbyshootingguns,

causingexplosions,orburningchemicals,thesmokeofwhichwassupposed

tocauseraintofall.Theserainmakersaskedforasmuchas1,000dollars

tomakeaninchofrain.Onewassoeffectivethathewasalmosthanged.

Hewasbelievedtohavecausedatwenty-inchraininsouthernCalifornia

thatfloodedtheland,killedseveralpeople,anddidmillionsofdollars'

worthofdamage.

Before1946,rainmakerswereeitherliarsorhonestpeoplewhohappened

tohavegoodluck.Scientificrainmakingwasstartedinthatyearby

VincentJ.Schaefer,ascientistatthelaboratoriesoftheGeneral

ElectricCompanyinNewYorkState.Hissuccesswastheresultofalucky

accidentthatchangedyearsoffailureintovictory.

Foralongtime,menhaveunderstoodwhereraincomesfrom.Waterfrom

thesurfaceofoceansandlakesbecomespartoftheair,whereitforms

cloudsfromwhichrainfalls.Butexactlywhatstartstheformationof

raindropswasnotknownuntilquiterecently.AmannamedJohnAitken

provedthatdropsofwatergatheraroundtinybitsofdustorothermatter.

Thecentersofthedropsaresosmallthatthehumaneyecannotseethem.

Withoutsuchcenters,itseems,raindropsdonotform.

DuringWorldWarII,Dr.IrvingLangmuir,ascientist,washiredbythe

GeneralElectricCompanytostudyhowandwhyiceformsonthewingsof

airplanes.HeandayoungassistantnamedSchaeferwenttoamountainin

thestateofNewHampshire,wheresnowstormsarecommonandcoldwinds

blow.

WhileinNewHampshire,LangmuirandSchaeferweresurprisedtolearnthat

oftenthetemperatureofthecloudssurroundingthemwasfarbelowthe

freezingpoint,andyeticedidnotformintheclouds.AftertheWar,

Schaeferexperimentedwithamachinethatcreatedcold,moistairsimilar

totheairfoundinclouds.Toimitatethemoistairofacloud,Schaefer

wouldbreatheintothemachine.Thenhewoulddropintothefreezerabit

ofpowder,sugar,orsomeothersubstance.Forweeksandmonthshetried

everythinghecouldimagine.Nothinghappened.Nocrystalsoficewere

formed.Noneofthesubstanceswouldserveasthecenterofasnowcrystal

orraindrop.

OneJulymorning,Schaeferwasdroppinginbitsofvarioussubstancesand

watchingtheunsuccessfulresults.Finally,afriendsuggestedthatthey

gotoeatlunch,andSchaefergladlywentwithhim.Asusual,heleftthe

coverofthefreezerup,sincecoldairsinksandwouldnotescapefrom

thebox.

Returningfromlunch,Schaeferwasbeginningtoperformhisexperiments

againwhenhehappenedtolookatthetemperatureofthefreezer.Ithad

risentoapointhigherthanthatrequiredforicecrystalstoremainsolid.

Thewarmsummerweatherhadarrivedwithouthisnoticingit.Hewouldhave

tobemorecarefulinthefuture.

Thereweretwochoicesnow.Hecouldclosethecoverandwaitforthe

freezeritselftolowertheairtemperature,orhecouldmaketheprocess

occurfasterbyaddingdryice,agasinsolidformthatisvery,very

cold.Hechosethelatterplan.Hedecidedtotryacontainerofdryice.

Ashedroppedthesteamingwhitedryiceintothefreezer,hehappened

tobreatheoutalargeamountofair.Andthere,beforehiseyes,it

happened!Hehadmadeicecrystals,notbyaddingcenterstothemoisture

butbycoolingthebreathsomuchthattheliquidhadtoformcrystals!

Schaefercalledtohishelperstocomeandwatch.Thenhebegantoblow

hisbreathintothefreezeranddroplargepiecesofdryicethroughit

tocreatecrystalswhichbecameatinysnowstormfallingslowlytothe

floorofhislaboratory.

Ifhecouldmakesnowinafreezer,Schaeferthought,whycouldn，thedo

soinarealcloud?Hedecidedtotryitinanairplanewithamachine

toblowdryiceoutintotheclouds.

OnacolddayinNovember,SchaeferandLangmuirsawcloudsinthesky,

andSchaeferclimbedintotheairplane.Herealizedhewouldhavetofly

somedistancebeforefindingtherightkindofcloud—abiggrayonethat

mustbefilledwithmoisture.Seeingone,Schaefertoldthepilotofthe

planetoflyabovethecloud.Atthepropertime,hestartedthemachine,

anddryicebegantofallfromtheairplaneintothecloudbelow.When

halftheloadofdryicewasgone,themotorstoppedbecauseithadbecome

toocold.Schaeferhadtothinkquickly.Hemerelythrewtheremaining

dryiceoutofthewindowoftheplane•80•

andintothecloudbelow.

Ontheground,Dr.Langmuirwatchedexcitedlyandsawsnowfallingfrom

thebottomofthecloud.WhenSchaeferreturnedtotheground,bluewith

cold,Langmuirrantohim,shouting,“Youhavemadehistory!”Andindeed

hehad.Almostassoonasthenewsofhisaccomplishmentwassentacross

theUnitedStatesandaroundtheworld,ahundredotherrainmakerswere

throwingdryiceintoclouds—or"seedingtheclouds"asitwascalled.

WhenSchaeferdiscoveredthaticecrystalscouldbeformedwithoutfinding

therightmaterialtomakecentersforthecrystals,hestoppedsearching

forsuchmaterials.ButanotheryoungworkeratGeneralElectric,Bernard

Vonnegutbeganlookingthroughachemistrybookforsomechemicalcompound

thatmighthavetherightsizeandshapetoformcrystalsaroundit.He

foundwhathewasbookingfor.Itwasacompoundcalledsilveriodide（碘

化车艮）.Hegotsomesilveriodideanddevelopedawayofburningitto

producetinyparticlesthatwouldseparateintheairandformsnow-

hehoped.

Finallyheshotthematerialupintotheairandwaitedforthestorm.

Nothinghappened.Hecouldn'tunderstandwhy.Thecompoundoughttoform

entersforcrystals.Heaskedascientisttoexaminethechemicalshehad

used.Therewasthetrouble.Thesilveriodidehehadusedwasnotpure.

Hegotmoreofthematerial,performedhisexperimentagain,andthere

werethesnowcrystals!Today,scientificrainmakersgenerallyusesilver

iodide,Whichcanbesentintotheairfromthegroundbymeansofasimple,

inexpensivemachine.Thisprocessismoresatisfactorythantheuseof

dryicewhichcanbedestructive.

1.Humanbeingswereabletomakeraininancienttimes.

2.Dr.IrvingLangmuirandSchaeferwenttoNewHampshiretostudyhow

andwhyiceformsonthewingsofairplanes.

3.Schaeferfoundouttheraindropscouldbemadewithouthavingto

searchtherightmaterialtomaketheircenters.

4.Usingsilveriodidetomakerainismoresatisfactorythanusingdry

ice.

5.Raincanbemadebyshootingsaltontotheclouds.

6.Schaeferfoundthewarmsummerweatherwasfavorableforrainmaking.

7.BernardVonnegutlookedthroughachemistrybooktofindwhethersilver

iodidewastherightmaterialformakingrain.8.Schaefersucceededin

makingicecrystalsbycoolingthebreathsomuchthattheliquid

crystals.

9.InNewHampshireSchaeferexperimentedwithamachinecreatingcold,

moistair

similartotheairorothermatter.

10.AccordingtoJohnAitken,waterdropsgatheraround_

Passage2

Asthe11oflifecontinuestoincrease,wearefastlosingtheartof

relaxation.Onceyouareinhabitofrushingthroughlife,beingonthe

gofrommorningtillnight,itishardtoslowdown.Butrelaxationis

essentialforahealthymindandbody.

Stressisanaturalpartofeverydaylifeandthereisnowaytoavoid

it.Infact,itisnotthebadthingitisoften12tobe.Acertainamount

ofstressis13toprovidemotivationandgivepurposetolife.Itisonly

whenthestressgetsoutofcontrolthatitcanleadtopoor14

andillhealth.

Theamountofstressapersoncan15dependsverymuchontheindividual.

Somepeoplearenotafraidofstress,andsuchcharactersare16prime

materialformanagerialresponsibilities.Othersloseheartatthefirst

signsof17difficulties.Whenexposedtostress,inwhateverform,we

reactbothchemicallyandphysically.Infactwemakechoicebetween

“fight"or"flight"andinmoreprimitivedaysthechoicesmadethe

differencebetweenlifeordeath.Thecriseswemeettodayareunlikely

tobeso18,buthoweverlittlethestress,itinvolvesthesameresponse.

Itiswhensuchareactionlastslong,throughcontinued19tostress,

thathealthbecomesendangered.Suchseriousconditionsashighblood

pressureandheartdiseasehaveestablished1inkswithstress.Sincewe

cannot20stressfromour1ives(itwouldbeunwisetodosoevenifwe

could),weneedtofindwaystodealwithit.

AcancelB.paceC.extremeD.

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Passage3

Intheearlydaysofnuclearpower,theUnitedStatesmakemoneyonit.

Buttodayopponents（反对者）havesocomplicateditsdevelopmentthat

nonuclearplantshavebeenorderedorbuiltherein12years.

Thegreatestfearofnuclearpoweropponentshasalwaysbeenareactor

“meltdown”.Today,thechancesofameltdownthatwou1dthreatenU.S.

publichealthareverylittle.Buttoevenfurtherreducethepossibility,

engineersaretestingnewreactorsthatrelynotonhumanjudgmenttoshut

themdownbutonthelawsofnature.NowGeneralElectricisalready

buildingtwoadvancedreactorsinJapan.Butdon，texpectthemevenon

U.S.shoresunlessthingschangeinWashington.

Theprocedureforlicensingnuclearpowerplantsisabaddream.Anytime

during,orevenafter,construction,anobjectionbyanygroupor

individualcanbringeverythingtoahaltwhilethematterisinvestigated

ortakentocourt.Meanwhile,thebuildermustaddnice-but-not-necessary

improvements,someofwhichforcehimtoknockdownwallsandstartover.

Ineverycasewhenaplanthasbeenopposed,theNuclearRegulation

Commissionhasultimatelygrantedalicensetoconstructoroperate.But

thevictoryoftencostssomuchthattheutilityendsupabandoningthe

plantanyway.

AcaseinpointistheShorehamplantonNewYork，sLongIsland.Shoreham

wasavirtualtwintotheMillstoneplantinConnecticut,bothordered

inthemid-60's.Millstone,completedfor$101million,hasbeen

generatingelectricityfortwodecades.Shoreham,however,wassingled

outbyantinuclearactivistswho,bysendinginendlessprotests,drove

thecostover$5billionanddelayeditsuseformanyyears.

Shorehamfinallywonitsoperationlicense.Buttheplanthasnever

producedawattpower.GovernorMarioCuomo,anopponentofaShoreham

startup,usedhispowertoforceNewYork,spublic-utilitiescommission

toacceptthefollowingsettlement:thepowercompanycouldpassthecost

ofShorehamalongtoitsconsumersonlyifitagreednottooperatethe

plant.I'oday,aperfectlygoodfacility,capableofservicinghundreds

ofthousandsofhomes,sitsrusting.

21.Theauthor'sattitudetowardthedevelopmentofnuclearpoweris.

A.negativeB.neutral

C.positiveD.

questioning

22.Whathasmadetheprocedureforlicensingnuclearpowerplantsabad

dream?

A.TheinefficiencyoftheNuclearRegulationCommission.B.Theenormous

costofconstructionandoperation.

C.Thelengthoftimeittakestomakeinvestigations.

D.Theobjectionoftheopponentsofnuclearpower.

23.ItcanbeinferredfromParagraph2that.

A.therearenotenoughsafetymeasuresintheU.S.forrunningnew

nuclearpowerplants

B.itisnottechnicaldifficultiesthatpreventthebuildingofnuclear

powerplantsintheU.S.

C.therearealreadymorenuclearpowerplantsthannecessaryinthe

U.S.

D.theAmericangovernmentwillnotallowJapanesenuclearreactorsto

beinstalledintheU.S.

24.GovernorMarioCuomo'schiefintentioninproposingthesettlement

wasto.

A.stoptheShorehamplantfromgoingintooperation

B.urgethepowercompanytofurtherincreaseitspowersupply

C.permittheShorehamplanttooperateundercertainconditions

D.helpthepowercompanytosolveitsfinancialproblems

25.Thephrase"singleout"isclosestinmeaningto.

A.delayB.end

up

C.completeD.

separate

Passage4

Waterproblemsinthefuturewillbecomemoreintenseandmorecomplex.

Ourincreasingpopulationwilltremendouslyincreaseurbanwastes,

primarilysewage.Ontheotherhand,increasingdemandsforwaterwill

decreasesubstantiallytheamountofwateravailablefordilutingwastes.

Rapidlyexpandingindustrieswhichinvolvemoreandmorecomplexchemical

processeswillproducelargevolumesofliquidwastes,andmanyofthese

willcontainchemicalswhicharepoisonous.Tofeedourrapidlyexpanding

population,agriculturewillhavetobeintensified.Thiswillinvolve

ever-increasingquantitiesofagriculturechemicals.Fromthis,itis

apparentthatdrasticstepsmustbetakenimmediatelytodevelop

correctivemeasuresforthepollutionproblem.

Therearetwowaysbywhichthispollutionproblemcanbelessened.The

firstrelatestothetreatmentofwastestodecreasetheirpollutionhazard.

Thisinvolvestheprocessingofsolidwastes"priorto"disposalandthe

treatmentofliquidwastes,oreffluents（废料），topermitthereuseof

thewaterorbestreducepollutionuponfinaldisposal.

Asecondapproachistodevelopaneconomicuseforallorapartofthe

wastes.Farmmanureisspreadinfieldsasanutrient（养料）ororganic

supplement.Effluentsfromsewagedisposalplantsareusedinsomeareas

bothforirrigationandforthenutrientscontained.Effluentsfromother

processingplantsmayalsobeusedasasupplementalsourceofwater.Many

industries,suchasmeatandpoultryprocessingplants,arecurrently

convertingformerwasteproductionintomarketablebyproducts.Other

industrieshavepotentialeconomicusesfortheirwasteproducts.

26.Thepurposeofthispassageis.

A.towarnthereaderofthedwindlingwatersupply

B.toexplainindustrialusesofwater

C.toacquaintthereaderwithwaterpollutionproblems

D.todemonstratevariousmeasurestosolvethepollutionproblemWhich

ofthefollowingpointsisnotincludedinthepassage?

A.Industrialdevelopmentincludesthesimplificationofcomplex

chemicalprocesses.

B.Dilutingwastesneedscertainamountofwater.

C.Demandsforwaterwillgoupalongwiththeexpandingpopulation.

D.Intensivecultivationoflandrequiresmoreandmorechemicals.The

readercanconcludethat.

A.countriesoftheworldwillworktogetheronpollutionproblems

B.byproductsfromwastesleadtoamoreprosperousmarketplace

C.scienceismakinggreatprogressonincreasingwatersupplies

D.someindustriesarenowmakingeconomicuseofwastes

Theauthorgivessubstancetothepassagethroughtheuseof.

A.interviewswithauthoritiesinthefieldofwatercontrols

B.opinionandpersonalobservations

C.definitionswhichclarifyimportantterms

D.strongargumentandpersuasions

Thewords"priorto”(Para.2)probablymean.

A.afterB.during

C.beforeD.beyond

二、完型填空

Moreandmorestudentswanttostudyin"hot"majors.1aresult,many

studentswantto2theirinterestsandstudyinthese3suchasforeign

languages,internationalbusinessandlaw,etC.Fewerandfewerstudents

choosescientificmajors,4maths,physicsandbiology,andartmajors,

5history,Chineseandphilosophy.6studentscanstudyinthese"hot"

majors,becausethenumberofthese"hot"majors7limiteD.Ifone8

interestinhisworkorstudy,9canhedowell?I10thisfromoneof

myclassmates.Heis11thecountryside.Hisparentsarefarmers.Though

he12biology,hechose(<internationalbusiness”.He13tolivealife

whichisdifferent14ofhisparents.Intheend,hefoundhe15indoing

business.Hefoundallthesubjectstobe16.17thiswouldn'thave

happenedifhehadchosenhismajoraccordingtohisowninterests.

Choosingamajorinuniversity18decideone'swholelife.Majors19are

not"hot"todaymaybecomethe"hot"majoroftomorrow.Choosingyour

majoraccordingtoyourown20isthebestwaytosucceeD.

1.A.BeingB.ForC.HavingD.As

2.A.giveupB.appearC.giveD.master

3.A.placeB.roomC.areasD.space

4.A.forexampleB.muchasC.andsoonD.asaresult

5.A.evenB.likeC.justD.or

6.A.OnlyafewB.QuiteafewC.PerhapsD.Many

7.A.isB.areC.wouldbeD.havebeen

8.A.hadnoB.hadC.hasnoD.has

9.A.whyB.andwhatC.howD.andhow

10.A.suggestedB.guessedC.searchedD.learned

11.A.outofB.offC.inD.from

12.A.studiedB.likesC.learnsD.succeedstostudy

13.A.wantsB.doesn,twantC.enjoysD.doesn'tlike

14.A.fromwhichB.fromthatC.forwhichD.forthat

15.A.wasinterestedB.wascleverC.wasnotinterestedD.wasnot

clever

16.A.lovelyB.rareC.obviousD.tiresome