2021年英語專業四級考試真題和答案分析一、聽力理解（ListeningComprehension）（一）對話（Conversations）對話1W:Hi,Mark.Iheardyouwenttoajobfairlastweek.Howwasit?M:Well,itwasamixed-bag.Therewerealotofcompaniesthere,butmostofthepositionswerenotreallywhatI'mlookingfor.I'minterestedinsoftwaredevelopment,andonlyafewcompanieswereofferingrelevantjobs.W:That'stoobad.Didyousubmitanyresumes?M:Yeah,Ihandedoutaboutfiveresumes.Oneofthecompaniesseemedreallyinterestedinme.Theyaskedmetocomeforaninterviewnextweek.W:Great!That'sagoodstart.Whatkindofquestionsdoyouthinkthey'llaskintheinterview?M:I'mnotsure.Maybethey'llaskaboutmyprogrammingskills,myexperiencewithdifferentprogramminglanguages,andmyproblem-solvingabilities.I'mgoingtoreviewsomeofthekeyconceptsandpracticesomecodingproblemsthisweek.1.WhatwasMark'simpressionofthejobfair?A.Itwasacompletefailure.B.Itwasjustso-so.C.Itwasexcellent.D.Itwasworsethanexpected.答案：B。從Mark所說的“Well,itwasamixed-bag”可以看出他覺得招聘會有好有壞，也就是一般般，所以選B。2.HowmanyresumesdidMarkhandoutatthejobfair?A.Three.B.Four.C.Five.D.Six.答案：C。文中明確提到“Yeah,Ihandedoutaboutfiveresumes”，所以答案是C。3.WhatwillMarkdothisweek?A.Waitfortheinterviewresults.B.Reviewsomekeyconceptsandpracticecoding.C.Lookformorejobfairs.D.Learnanewprogramminglanguage.答案：B。根據“I'mgoingtoreviewsomeofthekeyconceptsandpracticesomecodingproblemsthisweek”可知選B。對話2W:Hello,thisisthecustomerservice.HowcanIhelpyou?M:I'mcallingaboutthelaptopIboughtfromyourstorelastmonth.It'sbeengivingmealotofproblems.W:I'msorrytohearthat.Canyoutellmewhatkindofproblemsyou'rehaving?M:Well,thescreenkeepsgoingblack.Sometimesitcomesbackonafterafewseconds,butsometimesIhavetorestartthelaptop.Andalso,thebatterydoesn'tlastverylong.W:Isee.We'llneedtogetyourlaptopbacktoourrepaircenter.Canyoubringittoourstorethisweekend?M:I'mreallybusythisweekend.CanIsendittoyoubymail?W:Sure.We'llprovideyouwithareturnshippinglabel.Justpackthelaptopcarefullyandattachthelabel.We'llstarttherepairprocessassoonaswereceiveit.4.Whatisthemainproblemwiththelaptop?A.Thekeyboarddoesn'twork.B.Thescreengoesblack.C.Theharddriveisbroken.D.Thesoundisnotclear.答案：B。男士提到“Well,thescreenkeepsgoingblack”，這是主要問題，所以選B。5.Howwillthemansendthelaptoptotherepaircenter?A.Bybringingittothestoreinperson.B.Byusingacourierservice.C.Bymail.D.Byaskingafriendtodeliverit.答案：C。男士說“CanIsendittoyoubymail?”，客服表示同意，所以選C。（二）短文（Passages）短文1Theimportanceofsleepcannotbeoverstated.Sleepisavitalprocessthatallowsourbodiesandmindstorestandrecover.Duringsleep,ourbodiesrepairdamagedcells,consolidatememories,andregulatehormones.Lackofsleepcanhaveseriousconsequencesforourhealth.Studieshaveshownthatpeoplewhodon'tgetenoughsleeparemorelikelytodevelopchronicconditionssuchasobesity,diabetes,andheartdisease.Sleep-deprivedindividualsalsotendtohavelowerimmunefunction,makingthemmoresusceptibletoinfections.Inadditiontophysicalhealth,sleepalsoaffectsourmentalwell-being.Peoplewhoaresleep-deprivedoftenexperiencemoodswings,irritability,anddifficultyconcentrating.Theymayalsobeatahigherriskofdevelopingmentalhealthdisorderssuchasdepressionandanxiety.Toensuregoodsleep,itisimportanttoestablisharegularsleepschedule.Gotobedandwakeupatthesametimeeveryday,evenonweekends.Createacomfortablesleepenvironmentthatisdark,quiet,andcool.Avoidusingelectronicdevicesbeforebedtime,asthebluelightemittedbythesedevicescaninterferewithsleep.6.Whatdoesthepassagemainlytalkabout?A.Thebenefitsofexercise.B.Theimportanceofsleep.C.Thecausesofobesity.D.Theeffectsofstress.答案：B。文章開頭就指出“Theimportanceofsleepcannotbeoverstated”，隨后圍繞睡眠的重要性展開，包括對身體和心理健康的影響以及如何保證良好睡眠，所以選B。7.Whichofthefollowingisaconsequenceoflackofsleep?A.Improvedimmunefunction.B.Lowerriskofheartdisease.C.Moodswings.D.Betterconcentration.答案：C。文中提到“Peoplewhoaresleep-deprivedoftenexperiencemoodswings,irritability,anddifficultyconcentrating”，所以選C。8.Howcanweensuregoodsleepaccordingtothepassage?A.Stayuplateonweekends.B.Useelectronicdevicesbeforebedtime.C.Establisharegularsleepschedule.D.Keepthebedroombright.答案：C。根據“Toensuregoodsleep,itisimportanttoestablisharegularsleepschedule”可知選C。短文2TheAmazonrainforestisoneofthemostbiodiverseregionsonEarth.Itishometomillionsofplantandanimalspecies,manyofwhicharefoundnowhereelseintheworld.TherainforestplaysacrucialroleinregulatingtheEarth'sclimate.Itabsorbslargeamountsofcarbondioxide,agreenhousegasthatcontributestoglobalwarming.However,theAmazonrainforestisunderthreat.Deforestationisthebiggestproblem.Loggingcompaniesarecuttingdownlargeareasoftreesfortimber.Farmersareclearinglandforagriculture,especiallyforcattleranching.Thisdeforestationnotonlydestroysthehabitatofmanyspeciesbutalsoreleaseslargeamountsofcarbondioxideintotheatmosphere,acceleratingglobalwarming.ConservationeffortsarebeingmadetoprotecttheAmazonrainforest.Governments,environmentalorganizations,andlocalcommunitiesareworkingtogethertoenforcelawsagainstillegalloggingandpromotesustainablelanduse.Theyarealsotryingtoraiseawarenessabouttheimportanceoftherainforest.9.WhatistheroleoftheAmazonrainforestintheEarth'sclimate?A.Itreleaseslargeamountsofcarbondioxide.B.Itabsorbscarbondioxide.C.Itcausesglobalwarming.D.Ithasnoimpactontheclimate.答案：B。文中提到“Itabsorbslargeamountsofcarbondioxide,agreenhousegasthatcontributestoglobalwarming”，所以選B。10.WhatisthebiggestthreattotheAmazonrainforest?A.Forestfires.B.Deforestation.C.Pollution.D.Over-hunting.答案：B。根據“However,theAmazonrainforestisunderthreat.Deforestationisthebiggestproblem”可知選B。11.WhoisinvolvedintheconservationeffortsoftheAmazonrainforest?A.Onlygovernments.B.Onlyenvironmentalorganizations.C.Governments,environmentalorganizations,andlocalcommunities.D.Scientistsonly.答案：C。文中說“Governments,environmentalorganizations,andlocalcommunitiesareworkingtogethertoenforcelawsagainstillegalloggingandpromotesustainablelanduse”，所以選C。（三）新聞（NewsBroadcasts）新聞1Amajorearthquakestruckoffthecoastofasmallislandnationearlythismorning.Theearthquake,whichmeasured7.2ontheRichterscale,causedwidespreaddamage.Manybuildingsinthecoastalareascollapsed,andtherehavebeenreportsofcasualties.Rescueteamshavebeendispatchedtotheaffectedareas.Theyareworkinghardtosearchforsurvivorsandprovidemedicalassistancetotheinjured.Thegovernmenthasdeclaredastateofemergencyandiscallingforinternationalaidtohelpwiththerecoveryefforts.12.Whatwasthemagnitudeoftheearthquake?A.6.2.B.7.2.C.7.5.D.8.2.答案：B。文中明確提到“Theearthquake,whichmeasured7.2ontheRichterscale”，所以選B。13.Whathasthegovernmentdone?A.Ithascanceledthestateofemergency.B.Ithasrefusedinternationalaid.C.Ithasdeclaredastateofemergencyandcalledforinternationalaid.D.Ithasnottakenanyactionyet.答案：C。根據“Thegovernmenthasdeclaredastateofemergencyandiscallingforinternationalaidtohelpwiththerecoveryefforts”可知選C。新聞2AnewstudyhasfoundthatairpollutionislinkedtoanincreasedriskofAlzheimer'sdisease.Thestudy,whichwasconductedoveraperiodofseveralyears,followedthousandsofparticipants.Theresearchersfoundthatpeoplewhowereexposedtohighlevelsofairpollution,especiallyfineparticulatematter,hadahigherriskofdevelopingAlzheimer'sdiseasecomparedtothosewhowereexposedtolowerlevelsofpollution.Theexactmechanismbywhichairpollutionaffectsthebrainisstillnotfullyunderstood,butitisbelievedthatthepollutantscancauseinflammationinthebrain.14.Whatisthefindingofthenewstudy?A.AirpollutionislinkedtoalowerriskofAlzheimer'sdisease.B.AirpollutionislinkedtoanincreasedriskofAlzheimer'sdisease.C.ThereisnolinkbetweenairpollutionandAlzheimer'sdisease.D.Airpollutiononlyaffectsthelungs.答案：B。文中提到“AnewstudyhasfoundthatairpollutionislinkedtoanincreasedriskofAlzheimer'sdisease”，所以選B。15.WhatkindofairpollutionisespeciallyrelatedtotheriskofAlzheimer'sdisease?A.Ozone.B.Sulfurdioxide.C.Fineparticulatematter.D.Carbonmonoxide.答案：C。根據“Theresearchersfoundthatpeoplewhowereexposedtohighlevelsofairpollution,especiallyfineparticulatematter,hadahigherriskofdevelopingAlzheimer'sdisease”可知選C。二、詞匯與語法（VocabularyandGrammar）16.Theprofessorgaveavery______lectureonthehistoryofart.A.informingB.informedC.informativeD.informable答案：C。“informative”意為“信息豐富的，有教益的”，用來形容講座很合適；“informing”一般不用于修飾名詞；“informed”意為“有見識的，明智的”；“informable”不是常見詞匯。所以選C。17.He______hisnewjobwithgreatenthusiasm.A.tookupB.tookoverC.tookinD.tookoff答案：A。“tookup”有“開始從事，拿起”等意思，“tookuphisnewjob”表示“開始從事他的新工作”；“tookover”是“接管”；“tookin”有“吸收，理解，收留”等意思；“tookoff”是“起飛，脫下”。所以選A。18.Thecompanyisfacing______financialdifficulties.A.considerateB.considerableC.consideredD.considering答案：B。“considerable”意為“相當大的，相當多的”，“considerablefinancialdifficulties”表示“相當大的財政困難”；“considerate”是“體貼的，考慮周到的”；“considered”是“經過深思熟慮的”；“considering”是介詞，意為“鑒于，考慮到”。所以選B。19.______hehadforgottentobringhistextbook.A.ItseemedthatB.ThatseemedC.ItseemsD.Thatseems答案：A。“Itseemedthat...”是固定句型，表示“似乎……”，根據語境這里應該用過去時態，所以選A。20.Thecommitteeconsists______tenmembers.A.inB.ofC.withD.by答案：B。“consistof”是固定短語，意為“由……組成”，所以選B。21.Sheistheonlyoneofthestudentswho______passedtheexam.A.haveB.hasC.areD.is答案：B。在“oneof+復數名詞+定語從句”結構中，若one前有theonly等修飾，定語從句的謂語動詞用單數形式，這里是“haspassed”，所以選B。22.______hisillness,hedidn'tgotoschoolyesterday.A.BecauseB.DuetoC.OwingtoD.Thanksto答案：C。“owingto”可用于句首或句中，引出造成某種后果的原因，這里表示“由于他生病，他昨天沒去上學”；“because”引導原因狀語從句；“dueto”一般不用于句首；“thanksto”通常表示“多虧，由于（好的原因）”。所以選C。23.Thebookiswell-writtenand______worthreading.A.veryB.quiteC.ratherD.well答案：D。“wellworthdoing”是固定表達，意為“很值得做某事”，所以選D。24.He______beathomenowbecausehiscarisinthedriveway.A.mustB.canC.mayD.might答案：A。“must”表示肯定推測，根據“hiscarisinthedriveway”可以肯定他現在一定在家，所以選A。25.Theproblem______atthemeetingtomorrowisveryimportant.A.discussedB.beingdiscussedC.tobediscussedD.discussing答案：C。“tobediscussed”表示將來要被討論，根據“tomorrow”可知這里是指明天會議上要被討論的問題，所以選C。26.I'dratheryou______methetruthearlier.A.tellB.toldC.hadtoldD.wouldtell答案：C。“I'drather”后面的從句要用虛擬語氣，若表示與過去事實相反，從句用過去完成時，這里表示希望對方早點告訴我真相，與過去事實相反，所以選C。27.Theoldmanwalkedslowly,supported______hiswalkingstick.A.byB.withC.onD.in答案：A。“besupportedby”表示“被……支撐”，這里說老人被拐杖支撐著慢慢走，所以選A。28.Thenewpolicywillhaveagreatimpact______theeconomy.A.inB.onC.withD.at答案：B。“haveanimpacton”是固定短語，意為“對……有影響”，所以選B。29.______isknowntoall,theearthisround.A.AsB.ThatC.WhichD.It答案：A。“asisknowntoall”是固定用法，意為“眾所周知”，as引導非限定性定語從句，可置于句首，所以選A。30.Theteacher,togetherwithhisstudents,______goingtothemuseum.A.areB.isC.wereD.havebeen答案：B。當主語后面跟有“togetherwith”等連接的短語時，謂語動詞的單復數形式取決于主語本身，這里主語是“Theteacher”，是單數，所以選B。三、完型填空（Cloze）TheInternethasbecomeanimportantpartofourlives.Ithaschangedthewaywecommunicate,work,andlearn.However,likeanyothertechnology,theInternethasits31.Oneofthemainproblemsiscyber-bullying.Cyber-bullyingreferstotheuseoftheInternet,mobilephones,orotherdigitaltechnologiesto32others.Itcantakemanyforms,suchassendingmeanmessages,spreadingrumors,orpostingembarrassingphotosorvideos.Cyber-bullyingcanhaveserious33onthevictims.Theymayexperienceanxiety,depression,andlowself-esteem.Insomecases,itcanevenleadtosuicide.To34cyber-bullying,parents,schools,andsocietyneedtoworktogether.Parentsshouldmonitortheirchildren'sInternetuseandteachthemaboutthe35ofgoodonlinebehavior.Schoolsshouldhaveanti-bullyingpoliciesinplaceandprovidesupporttothevictims.Societyshouldalsoraiseawarenessaboutcyber-bullyingandcreateaculturethat36respectandkindness.AnotherproblemwiththeInternetisinformationoverload.Withsomuchinformationavailableonline,itcanbedifficultto37whatistrueandwhatisfalse.Peoplemaybeexposedtofalsenews,misinformation,andpropaganda.Thiscanhaveanegativeimpactontheirdecision-makingand38.Todealwithinformationoverload,peopleneedtodevelopcriticalthinkingskills.Theyshouldlearnto39thesourceofinformation,checkforevidence,andevaluatethecredibilityoftheinformation.Theyshouldalsobe40aboutwhattheyshareontheInternettoavoidspreadingfalseinformation.31.A.advantagesB.disadvantagesC.functionsD.features答案：B。前文提到互聯網有積極影響，接著用“However”轉折，說明這里要說互聯網的缺點，“disadvantages”符合語境，所以選B。32.A.harmB.helpC.protectD.support答案：A。根據“Cyber-bullying”可知是用網絡技術傷害他人，“harm”意為“傷害”，所以選A。33.A.effectsB.effortsC.affectsD.afford答案：A。“haveaneffecton”是固定短語，意為“對……有影響”，這里說網絡欺凌對受害者有嚴重影響，所以選A。34.A.preventB.promoteC.provideD.pretend答案：A。后面提到各方要一起努力，目的是預防網絡欺凌，“prevent”意為“預防，防止”，所以選A。35.A.importanceB.unimportanceC.differenceD.similarity答案：A。家長應該教孩子良好網絡行為的重要性，“importance”符合文意，所以選A。36.A.encouragesB.discouragesC.cancelsD.ignores答案：A。社會應該營造一種鼓勵尊重和友善的文化，“encourages”意為“鼓勵”，所以選A。37.A.tellB.sayC.speakD.talk答案：A。“tell”有“辨別，區分”的意思，這里說很難區分網上信息的真假，所以選A。38.A.attitudeB.altitudeC.gratitudeD.latitude答案：A。虛假信息會對人們的決策和態度產生負面影響，“attitude”意為“態度”，所以選A。39.A.analyzeB.synthesizeC.criticizeD.paralyze答案：A。人們應該學會分析信息來源，“analyze”意為“分析”，所以選A。40.A.carefulB.carelessC.carefreeD.caring答案：A。人們應該謹慎對待在網上分享的內容，“becarefulabout”表示“對……小心，謹慎”，所以選A。四、閱讀理解（ReadingComprehension）（一）Inthedigitalage,readinghabitshaveundergonesignificantchanges.Withtheriseofe-booksandonlinereadingplatforms,moreandmorepeopleareturningtodigitalreading.However,traditionalprintbooksstillholdaspecialplaceintheheartsofmanyreaders.Oneoftheadvantagesofdigitalreadingisconvenience.Youcancarrythousandsofbooksinasinglee-readeroronyoursmartphone.Youcanaccessthemanywhere,anytime,aslongasyouhaveadeviceandanInternetconnection.Digitalbooksalsooftencomewithfeaturessuchasadjustablefontsize,highlighting,andnote-taking,whichcanenhancethereadingexperience.Ontheotherhand,printbooksofferadifferentkindofreadingexperience.Thefeelofthepaper,thesmelloftheink,andtheactofturningthepagescreateatactileandsensoryexperiencethatmanyreadersfindappealing.Printbooksarealsomoresuitablefordeepreading.Youarelesslikelytobedistractedbynotificationsorotherdigitaldistractionswhenyouarereadingaprintbook.Inaddition,printbookshavealongerlifespancomparedtodigitalbooks.Digitalfilescanbelostduetotechnicalproblems,softwareupdates,orchangesinfileformats.Printbooks,ontheotherhand,canlastforgenerationsifproperlystored.41.Whatisthemaintopicofthepassage?A.Thehistoryofreading.B.Thecomparisonbetweendigitalreadingandprintreading.C.Thedevelopmentofe-books.D.Theimportanceofreading.答案：B。文章主要對比了數字閱讀和紙質閱讀的優缺點，所以選B。42.Whichofthefollowingisanadvantageofdigitalreading?A.Itprovidesatactileexperience.B.Ithasalongerlifespan.C.Itismoreconvenient.D.Itislesslikelytocausedistractions.答案：C。文中提到“Oneoftheadvantagesofdigitalreadingisconvenience”，所以選C。43.Whyareprintbooksmoresuitablefordeepreading?A.Becausetheyhaveadjustablefontsize.B.Becausetheyaremorecolorful.C.Becausetheyarelesslikelytocausedistractions.D.Becausetheyarecheaper.答案：C。根據“Youarelesslikelytobedistractedbynotificationsorotherdigitaldistractionswhenyouarereadingaprintbook”可知選C。44.Whatcanwelearnaboutthelifespanofdigitalbooksandprintbooks?A.Digitalbookshavealongerlifespan.B.Printbookshavealongerlifespan.C.Theyhavethesamelifespan.D.Thepassagedoesn'tmentionit.答案：B。文中說“Inaddition,printbookshavealongerlifespancomparedtodigitalbooks”，所以選B。（二）Theartofpublicspeakinghasbeenaroundforcenturies.Itisanimportantskillthatcanhelpindividualscommunicateeffectively,influenceothers,andachievetheirgoals.Agoodpublicspeakerneedstohaveseveralqualities.Firstly,theyshouldhaveaclearandwell-organizedmessage.Theaudienceshouldbeabletounderstandthemainpointseasily.Secondly,agoodspeakershouldbeabletoengagetheaudience.Thiscanbedonethroughtheuseofstories,examples,andhumor.Thirdly,agoodspeakershouldhavegoodbodylanguage.Theyshouldstandtall,makeeyecontact,anduseappropriategestures.Preparingforaspeechisalsocrucial.Aspeakershouldresearchthetopicthoroughly,knowtheaudiencewell,andpracticethespeechmultipletimes.Theyshouldalsobepreparedforquestionsandbeabletoanswerthemconfidently.Therearedifferenttypesofpublicspeaking,suchasinformativespeeches,persuasivespeeches,andentertainingspeeches.Eachtypehasitsowncharacteristicsandrequirements.Forexample,aninformativespeechaimstoprovideinformationtotheaudience,whileapersuasivespeechaimstoconvincetheaudiencetotakeacertainaction.45.Whatisthemainideaofthepassage?A.Thehistoryofpublicspeaking.B.Theimportanceofpublicspeakingandthequalitiesofagoodspeaker.C.Thedifferenttypesofpublicspeaking.D.Howtoprepareforaspeech.答案：B。文章既強調了公眾演講的重要性，又闡述了一個好的演講者應具備的品質，所以選B。46.Whichofthefollowingisaqualityofagoodpublicspeaker?A.Havingacomplexandhard-to-understandmessage.B.Beingunabletoengagetheaudience.C.Havinggoodbodylanguage.D.Avoidingeyecontactwiththeaudience.答案：C。文中提到“Thirdly,agoodspeakershouldhavegoodbodylanguage.Theyshouldstandtall,makeeyecontact,anduseappropriategestures”，所以選C。47.Whyispreparingforaspeechcrucial?A.Becauseitmakesthespeakerlookmoreprofessional.B.Becauseithelpsthespeakertoresearchthetopicbetter.C.Becauseitensuresthatthespeakercancommunicateeffectivelyandhandlequestions.D.Becauseitallowsthespeakertousemorehumor.答案：C。根據“Preparingforaspeechisalsocrucial.Aspeakershouldresearchthetopicthoroughly,knowtheaudiencewell,andpracticethespeechmultipletimes.Theyshouldalsobepreparedforquestionsandbeabletoanswerthemconfidently”可知選C。48.Whatistheaimofapersuasivespeech?A.Toprovideinformationtotheaudience.B.Toentertaintheaudience.C.Toconvincetheaudiencetotakeacertainaction.D.Toshowoffthespeaker'sknowledge.答案：C。文中提到“whileapersuasivespeechaimstoconvincetheaudiencetotakeacertainaction”，所以選C。（三）Theworldisfacingawatercrisis.Thedemandforwaterisincreasingduetopopulationgrowth,urbanization,andindustrialization.Atthesametime,thesupplyoffreshwaterislimited.Oneofthesolutionstothewatercrisisiswaterconservation.Thiscanbedonebyreducingwaterwasteinhouseholds,industries,andagriculture.Forexample,inhouseholds,peoplecanfixleakyfaucets,usewater-efficientappliances,andcollectrainwater.Inindustries,companiescanrecycleandreusewaterintheirproductionprocesses.Inagriculture,farmerscanusedripirrigationsystemsinsteadoftraditionalfloodirrigation,whichcansavealargeamountofwater.Anothersolutionisdesalination.Desalinationistheprocessofremovingsaltandotherimpuritiesfromseawaterorbrackishwatertomakeitsuitableforhumanuse.Althoughdesalinationisaneffectivewaytoincreasethesupplyoffreshwater,itisalsoexpensiveandenergy-intensive.Watermanagementisalsoimportant.Governmentsandwaterauthoritiesshoulddevelopcomprehensivewatermanagementplans.Theseplansshouldincludemeasuressuchaswaterpricing,waterallocation,andwaterqualitymonitoring.49.Whatisthemaincauseofthewatercrisis?A.Thedecreaseinpopulation.B.Thereductioninindustrialactivities.C.Theincreaseinwaterdemandandthelimitedsupplyoffreshwater.D.Theimprovementinwaterconservation.答案：C。文中提到“Thedemandforwaterisincreasingduetopopulationgrowth,urbanization,andindustrialization.Atthesametime,thesupplyoffreshwaterislimited”，所以選C。50.Whichofthefollowingisawayofwaterconservationinhouseholds?A.Leavingfaucetsrunning.B.Usingwater-inefficientappliances.C.Fixingleakyfaucets.D.Wastingwateronunnecessarythings.答案：C。根據“inhouseholds,peoplecanfixleakyfaucets,usewater-efficientappliances,andcollectrainwater”可知選C。51.Whatisthedisadvantageofdesalination?A.Itisnoteffective.B.Itisexpensiveandenergy-intensive.C.Itcannotremoveallimpurities.D.Itisnotsuitableforhumanuse.答案：B。文中說“Althoughdesalinationisaneffectivewaytoincreasethesupplyoffreshwater,itisalsoexpensiveandenergy-intensive”，所以選B。52.Whatshouldgovernmentsandwaterauthoritiesdoaccordingtothepassage?A.Donothingaboutthewatercrisis.B.Developcomprehensivewatermanagementplans.C.Increasethepriceofwaterwithoutanyplan.D.Ignorewaterqualitymonitoring.答案：B。根據“Watermanagementisalsoimportant.Governmentsandwaterauthoritiesshoulddevelopcomprehensivewatermanagementplans”可知選B。五、寫作（Writing）（一）便條寫作（Note-writing）題目：YoureceivedaninvitationfromyourclassmateTomtohisbirthdaypartythisSaturday.Butyouhavealreadymadeanappointmentwithyourdentistonthatday.WriteanotetoTomtodeclinehisinvitationpolitely,expressyourregret,andwishhimahappybirthday.DearTom,I'mreallysorrythatIcan'tattendyourbirthdaypartythisSaturday.Ireceivedyourkindinvitationwithgreatpleasure,butunfortunately,Ihavealreadymadeanappointmentwithmydentistonthatday.Iknowyourbirthdaypartywillbealotoffun,andIreallywishIcouldbetheretocelebratewithyou.However,thedentalappointmentisquiteimportantasIhavebeenhavingsometoothproblemsrecently.Isincerelyhopeyouunderstandmysituation.Iwishyouaveryhappybirthdayandawonderfulparty.Mayallyourbirthdaywishescometrue!Yourssincerely,[YourName]（二）命題寫作（Composition）題目：S