2021年浙江省杭州市公共英語(yǔ)五級(jí)(筆試)測(cè)試卷(含答案)

2021年浙江省杭州市公共英語(yǔ)五級(jí)(筆試)測(cè)試卷(含答案)學(xué)校:________班級(jí):________姓名:________考號(hào):________

一、1.ListeningComprehension(15題)1.PartB

Directions:Youwillhear3conversationsortalksandyoumustanswerthequestionsbychoosingA,B,CorD.YouwillheartherecordingONLYONCE.

聽(tīng)力原文：M:Now,I'dliketosaythatIthinkthatthisgovernmentproposingtobuildmorenuclearpowerstationsinthiscountryisreallybeingstupid.Thepointaboutnuclearpoweristhatwehaven'tlearnttodoawaywiththewaste.Wehaven'tlearnttocopewiththewastefromityet.

W:Well,Isometimesthinkthat,youknow,they'vegotanimpossiblejob.ImeanalltheimpressionIgetisthatthereisnoalternative...well,that'stheimpressionIget.

M:No,no,noI...Idon'tagreewiththatatall.Thereareplentyofalternatives.There'sthesun...solarpower...thatisasourcethatisalwaysthere,wealwayshaveit.

W:Idon't...Idon'tquiteseewhatyou'regettingatactually,solarpower,what'sthat?

M:Well,theheatfromthesun,itcanbeusedinsolarpanelsonthetopsofhousesforheating,storinguppowertoheatwaterandtoheatthehouses,youknow,somesolarpanelsareinoperationalreadyandtheyaresavingmoney...

W:That'sagoodpointactually,butisitreallyviable,that,ImeanbecauseI'd...

M:SorryitmustbejAndtheonegreatadvantageisthatIcansee,ifthegovernmentsetupsmallunitstobuildsolarpanelsandtoinstallthem,itwouldbecreatingemploymentwhichwouldimprovetheunemploymentsituationandbringterrificadvantages.

W:IhaveheardthatinEngland,Imean,there'snotenoughsun,isthere?For,Imean,solarpanelshere?

M:Yes,well,that'snotquitetrue.I...thereisquiteabitofsun...youmaynotfeeltheactualheatofitonsomeoccasions.

W:No,youarerightthere!

M:Butthelightpowerfromthesunwill.

Whatdoesthemanthinkofthegovernment'spresentproposalaboutbuildingmorepowerstationsinthecountry?

A.It'sadangerousproposal.

B.It'sastupidproposal.

C.It'sanadvantageousproposal.

D.It'saviableproposal.

2.What'sthepercentageofstudentsinbusinessandmanagement?

3.Wherewastheinterviewconducted?

4.Wecanmakearound-the-worldflighttripfreeofchargeifwefinishreadingenoughbooks.

A.TrueB.Fasle

5.HowmanypeopledependonlocalriceandfoodinSouthAsiacurrently?

A.Morethan150millionpeople.

B.Lessthan150millionpeople.

C.About100millionpeople.

D.About120millionpeople.

6.WhereisLowTillFarmingbecomingpopular?

A.Inareaswithfewweedsandunwantedplants.

B.Inareaswithasevereshortageofwater.

C.Inareaslackinginchemicalfertilizer.

D.Inareasdependentonimportedfood.

7.PartC

Directions:Youwillhearatalk.Asyoulisten,answerthequestionsorcompletethenotesinyourtestbookletforQuestions21-30bywritingNOTMORETHANTHREEwordsinthespaceprovidedontheright.YouwillhearthetalkTWICE.

Younowhave1minutetoreadQuestions21-30.

聽(tīng)力原文：Todaywetakeitforgrantedthatthemailwillbedelivereddailyatourdoor．Butmanyyearsagoitmighthavebeenplacedinatreetrunkorunderneatharock．Intheearlydaysofthemailnoonecouldbesureaboutwhereorwhenitwouldarrive．

AtthesoutherntipofAfricatherewasonceapostofficeunderarock．IntheolddaystheroutefromEnglandtoIndiawasaroundtheCapeofGoodHope．Thejourneywasstormyanddangerous．Ittooksixlongmonths．Sailorsoftenwishedtosendmailhome．buttheyseldommetshipsboundbacktoEngland．Soatthecapethesailorswouldgoashore．Theyheadedforacertainlargestone．Onthestonewerescratchedthewords“Lookhereunderforletters．”Theywouldleavetheirlettersthere．knowingthatthenexthomeward-boundshipwouldstopandpickthemup．

TherewasanotherpostofficelikethisatthesoutherntipofSouthAmerica．Duringthegoldrushdays，boatssailedaroundCapeHorntoCalifornia．AtCapeHornwasakegnailedtoapost．Boatscomingfromtheeastcoastwouldsendasmallboatashoretothispostoffice．Theypickedupanylettersinthekeg．Atthesametimetheymailedlettershomethatboatssailingeastcouldpickup．

InthestateofWashingtonstandsthestumpofahugecedar．It，too，wasonceapostoffice．Settlersneededaplaceforthemailcarrierstoleavetheirletters．Theirhousesweresowidelyscatteredthatthemailcarriercouldnotreachallofthem．a(chǎn)ndthepostofficewasfarawayoverroughroads．Sothesettlersfoundatreethatstoodwhereseveraltrailscrossed．Theycutthetreedowntenfeetfromtheground．holloweditout．a(chǎn)ndcovereditwitharoof．Inside,theynailedarowofwoodenboxes．Eachboxwasmarkedwithafamily'sname．Themailcarriercouldleavelettersthereforeveryoneformilesaround．

ForthefirstfewyearsaftertheEnglishcolonistscarnetoAmerica，therewasnoregularpostalservice．Peoplegavetheirletterstoanytravelerwhohappenedtobegoingintherightdirection．Oftentheygavethemtoapeddleroratravelingshoemaker．Whenthetravelerreachedthetownwheretheletterwasgoing，hemightstopataninn．Hewouldleavethelettersthere．Buttheretheystayeduntilthepersontheywereaddressedtohappenedtocomebyandstoppedattheinn．

WhataboutplaceslikeVirginiawheretherewereveryfewinns?Peoplewhowishedtosendletterswouldleavethematoneofthelargeplantations．Theownersoftheplantationwouldthensendthelettersontoaneighbor．Theneighborwoulddothesame．Itwasaslowmailsystem．

Aftermanyyears，regularmailcarriersonhorsebackwerehired．Theywentfromonebigtowntoanother．BetweenNewYorkandBoston，forexample．therewasone“postrider”amonth．Hetraveledonlybydayandtooktwoweeksforthetrip．Oftenthepostriderleftallthemailforawholetownatacrossroadsstore．ItstilltookmanyweeksforalettertoreachthepersonItwasaddressedto．

Finally，abouttwohundredyearsago，BenjaminFranklinwasmadepostmasterforallthecolonies．Hisfirstactwastomakealongjourneytofindoutthebestroutesforcarryingthemail．Thenhesetupalineofpoststationbetweenthenorthernandsoutherncolonies．Heorderedhispostriderstotravelbynightaswellasbyday．

Franklin'spostriderscouldcarrymorelettersinashortertimefromonecolonytoanother．TheletterservicehelpedtheyoungAmericancolonieslearnmoreabouteachother．Theylearnedthattheywereallinterestedinthesamethings．Thisgavethemthefeelingofunitythatlaterhelpedthemwintheirindependence．

8.WangpreferstolivewithanEnglishfamily.

A.TrueB.Fasle

9.聽(tīng)力原文：DuringtheChristmasshoppingrushinLondon,theintriguingstorywasreportedofatrampwho,apparentlythroughnofaultofhisown,foundhimselflockedinawell-knownchainstorelateonChristmasEve.Nodoubtthestorewasfilledwithlast-minuteChristmasshoppersandthestaffweredeadbeatingandlongingtogethome.Presumablyallthepropersecuritychecksweremadebeforethestorewaslockedandtheylefttoenjoythethree-dayholidayuntroubledbycustomersdesperatetogetlast-minuteChristmaspresents.

Howeverthatmaybe,ourtrampfoundhimselfaloneinthestoreanddecidedtomakethebestofit.Therewasfood,drink,beddingandcampingequipment,ofwhichhemadegooduse.Theremustalsohavebeentelevisionsetsandradios.Thoughitwasnotreportedifhetookadvantageofthesefacilities,whentheshopre-opened,hewasdiscoveredinbedwithalargenumberofemptybottlesbesidehim.Heseemstohavebeenamanofgoodhumourandphilosophictemperament—asindeedvagrantsverycommonlyare.EveryoneelsewasenjoyingChristmas,sohesawnogoodreasonwhyheshouldnotdothesame.Hesubmitted,cheerfullyenough,tobeingtakenawaybythepolice.PerhapshehadabetterChristmasthanusual.Hewasputintoprisonforsevendays.Thejudgeawardednocompensationtothechainstoreforthefoodanddrinkourtramphadconsumed.Theyhad,inhisopinion,alreadyreceivedvaluablefreepublicityfromthecoveragethestoryreceivedinthenewspapersandontelevision.PerhapsthejudgehadagoodChristmastoo.

Thetrampwaslockedinthestore______

A.forhisownmistakes

B.duetoamisunderstanding

C.byaccident

D.throughanerrorofjudgment

10.Meatsalsocontainwater.

A.RightB.Wrong

11.Whatproblemdoesthemanthinkcanbesolvedifthegovernmentputupsmallunitstobuildsolarpanels?

A.Theheatsupply.

B.Theelectricsupply.

C.Thewatersupply.

D.Theunemploymentsituation.

12.WhichofthefollowingrecordsoftheUSfootballteamistrue?

A.Firstplaceinthe3rdworldCup.

B.Secondplaceinthe4thWorldCup.

C.Thirdplaceinthe1stWorldCup.

D.Fourthplaceinthe2ndWorldCup.

13.Thedietsofthepeopleinthethreeregionsaretotallydifferent.

A.TrueB.Fasle

14.Whatdoesthetalkmainlyconcern?

15.Whatdoes"Apersonwhoisledaroundbythenose"mean?

A.Apersonwholetshisinstinctguidehim.

B.Apersonwhohasnowillofhisown.

C.Apersonwhoisdecisive.

D.Apersonwhoisfullofimaginationandcreativity.

二、2.UseofEnglish(10題)16.

【C4】

17.(38)

18.

【C20】

19.

【C6】

20.

【C11】

21.

【C7】

22.

【C18】

23."Themoregadgetsthereare,the【C1】______thingsseemtoget."saidHonoreErvin,co-authorofTheEtiquetteGirls:ThingsYouNeedtoBeTold."Justbecauseit'sthere【C2】______yourdisposal,doesn’tmeanyouhavetouseit24/7."

Arecent【C3】______bymarketresearchcompanySynovateshowedthat70percentof1,000respondents【C4】______thepoorestetiquetteincellphoneusersoverotherdevices.Theworsthabit?Loudphoneconversationsinpublicplaces,or"cellyell,"【C5】______to72percentoftheAmericanspolled.

"Peopleuse【C6】______anywhereandeverywhere,"Ervinsaid."Atthemovies-turn【C7】______yourcellphone.Idon'twanttopay$10tobesittingnexttosomeguychitchattingtohisgirlfriend【C8】______hiscellphone."Thisrudenesshasdeterioratedpublicspaces,accordingtoLewFriedland,acommunicationprofessor【C9】______theUniversityofWisconsin-Madison.He【C10】______thelackofmannersakindofunconsciousrudeness,【C11】______manypeoplearenot【C12】______ofwhatthey'redoingortheothersaroundthem.

"Ithinkit'sreallynoticeableinanyplane,trainorbus【C13】______you'resubjectedagainstyourwill【C14】______someoneelse'sconversation,"hesaid."Youcanlistentointimatedetailsoftheiruncle'sillness,problemswiththeirloversand【C15】______they'rehavingforsinner.""It【C16】______what.wasapublic"commonspaceandstartsto【C17】______itupintosmallprivatespace."

Ashorttimeago,ifcellphoneusers【C18】______politelyaskedtotalkquietly,theywould【C19】______withchagrin,hesaid."Nowmoreandmorepeopleareessentiallytreatingyoulikeyoudon'tunderstandthatloudcellphoneuseis【C20】______inpublic."

【C1】

24.Pollutionisa"dirty"word.Topollutemeanstocontaminate—topsoilorsomethingbyintroducingimpuritieswhichmake【31】______unfitoruncleantouse.Pollutioncomesinmanyforms.Weseeit,smellit,【32】______it,drinkit,andstumblethroughit.Weliterallylivedinandbreathepollution,and【33】______surprisingly,itisbeginningto【34】______ourhealth,ourhappiness,andourcivilization.

Oncewethoughtofpollution【35】______meaningsimplythesmog—thechoking,stinging,dirty【36】______thathoversovercities.Butairpollution,whileitis【37】______themostdangerous,isonlyonetypeofcontaminationamongseveral【38】______attackthemostbasiclifefunctions.

Throughtheuncontrolleduseofinsecticides,manhaspollutedtheland,【39】______thewildlife.By【40】______sewageandchemicalsintoriversandlakes,wehavecontaminatedour【41】______water.Wearepollutingtheoceans,too,killingthefishand【42】______deprivingourselves【43】______aninvaluablefoodsupply.

Partoftheproblemisourexploding【44】______.Moreandmorepeopleareproducingmorewastes.Butthisproblemisintensifiedbyour"throw-away"technology.EachyearAmericans【45】______of7millionautos,20milliontonsofwastepaper,25millionpoundsoftoothpastetubesand48millioncans.Wethrowawaygumwrappers,newspapers,andpaperplates.Itisnolongerwiseto【46】______anything.Todayalmosteverythingisdisposable.【47】______ofrepairingatoasteroraradio,itiseasierandcheapertobuyanotheroneanddiscardtheold,even【48】______95percentofitspartsmaystillbefunctioning.Babydiapers,whichusedtobemadeofreusablecloth,arenowpaperthrowaway.Soonwewillwearclothingmadeof【49】______:"Wearitonceandthrowitaway"willbethesloganofthefashionableconsciousness.

Whereisthisalltoend?Areweturningtheworldintoagiganticdump,oristherehopethatwecansolvethepollutionproblem?【50】______,solutionsareinsight.Afewofthemarepositivelyingenious.

(31)

25."Down-to-earth"meanssomeoneorsomethingthatishonest,realisticandeasytodealwith.Itisapleasuretofind【31】______whoisdown-to-earth.Apersonwhoisdown-to-earthiseasytotalk【32】______andacceptsotherpeopleasequals.Adown-to-earthpersonisjustthe【33】______ofsomeonewhoactsimportantorproud.

Down-to-earthpersonsmaybe【34】______membersofsociety,ofcourse.Buttheydonotlettheirimportance"【35】______totheirheads".Theydonotconsiderthemselvestobebetterpersonsthan【36】______oflessimportance.Someonewhoisfilledwithhisownimportanceandpride,【37】______withoutcause,issaidtohave"hisnoseintheair".Thereis【38】______wayapersonwithhisnoseintheaircanbedown-to-earth.

Americans【39】______anotherexpressionthatmeansalmostthesameas"down-to-earth".Theexpressionis"both-feet-on-the-ground".Someone【40】______both-feet-on-the-groundisapersonwithagoodunderstanding【41】______reality.Hehaswhatiscalled"commonsense,"hemayhavedreams,【42】______hedoesnotallowthemtoblockhisknowledgeof【43】______isreal.

Theoppositekindof【44】______isonewhohashis"head-in-the-clouds".Amanwithhishead-in-the-cloudsisadreamer【45】______mindisnotintherealworld.

【46】______,suchadreamercanbebroughtbacktoearth.Sharpwordsfromteachercanusually【47】______aday-dreamingstudentdown-to-earth.

Usually,thepersonwhoisdown-to-earthisvery【48】______tohavebothfeetontheground.【49】______wehavebothourfeetontheground,whenwearedown-to-earth,weacthonestlyandopenly【50】______others.Ourlivesarelikethegroundbelowus,solidandstrong.

(31)

三、3.ReadingComprehension(15題)26.(79)

27.

Accordingtothepassage,whichofthefollowingisTRUE?

A.AllAmericansarepersuadednottogetvaccinatedthisyear.

B.Thebigproblemininnovatingfluvaccineproducingtechniqueishowtogrowvirusinanewway.

C.Morefluvaccinescannotbeproducedinashorttimebecauseprivatecompaniesrefusetoproducemore.

D.Fluvaccinesareeasierthanmostvaccinestoproducethroughcellcultures.

28.Beforeabigexam,asoundnight'ssleepwilldoyoubetterthanporingovertextbooks.That,atleast,isthefolkwisdom.Andscience,intheform.ofbehavioralpsychology,supportsthatwisdom.Butsuchbehavioralstudiescannotdistinguishbetweentwocompetingtheoriesofwhysleepisgoodforthememory.Onesaysthatsleepiswhenpermanentmemoriesform.Theothersaysthattheyareactuallyformedduringtheday,butthen"edited"atnight,toflushawaywhatissuperfluous.

Totellthedifference,itisnecessarytolookintothebrainofasleepingperson,andthatishard.Butafteradecadeofpainstakingwork,ateamledbyPierreMaquetatLiegeUniversityinBelgiumhasmanagedtodoit.TheparticularstageofsleepinwhichtheBelgiangroupisinterestedisrapideyemovement(REM)sleep,whenbrainandbodyareactive,heartrateandbloodpressureincrease,theeyesmovebackandforthbehindtheeyelidsasifwatchingamovie,andbrainwavetracesresemblethoseofwakefulness.Itisduringthisperiodofsleepthatpeoplearemostlikelytoreliveeventsofthepreviousdayindreams.

Dr.MaquetusedanelectronicdevicecalledPETtostudythebrainsofpeopleastheypracticedataskduringtheday,andastheysleptduringthefollowingnight.Thetaskrequiredthemtopressabuttonasfastaspossible,inresponsetoalightcomingoninoneofsixpositions.Astheylearnthowtodothis,theirresponsetimesgotfaster.Whattheydidnotknowwasthattheappearanceofthelightssometimesfollowedapattern—whatisreferredtoas"artificialgrammar".Yetthereductionsinresponsetimeshowedthattheylearntfasterwhenthepatternwaspresentthanwhentherewasnot.

Whatismore,thosewithmoretolearn(i.e.the"grammar",aswellasthemechanicaltaskofpushingthebutton)havemoreactivebrains.The"editing"theorywouldnotpredictthat,sincethenumberofirrelevantstimuliwouldbethesameineachcase.Andtoeliminateanydoubtsthattheexperimentalsubjectswerelearningasopposedtounlearning,theirresponsetimeswhentheywokeupwereevenquickerthanwhentheywenttosleep.

Theteam,therefore,concludedthatthenerveconnectionsinvolvedinmemoryarereinforcedthroughreactivationduringREMsleep,particularlyifthebraindetectsaninherentstructureinthematerialbeinglearnt.Sonow,ontheeveofthatcrucialtest,mathsstudentscansleepsoundlyintheknowledgethatwhattheywillrememberthenextdayarethebasicrulesofalgebraandnottheincoherenttalkfromtheradionextdoor.

Researchersinbehavioralpsychologyaredividedwithregardto______.

A.howdreamsaremodifiedintheircourses

B.thedifferencebetweensleepandwakefulness

C.whysleepisofgreatbenefittomemory

D.thefunctionsofagoodnight'ssleep

29.(77)

30.(76)

31.

WhatisNOTtrueabouttheeightgirls?

A.Theyareallbetween12and17.

B.Theyhavetriedavarietyofmeasures.

C.Theyattendasuicidesquad.

D.Alltheirattemptstocommitsuicidearevital.

32.

Whichofthefollowingstatementsistrue?

A.Americans'caloricintakehasdroppedoverthelastfewdecades.

B.Manypeoplewhotrytoloseweightgiveuphalfway.

C.Americansarealwaysawareofhowmuchtheyeat.

D.Obesitydoesnoharmtopeople'shealth.

33.(69)

34.

Theword“connoisseurs”(Paragraph1)mostprobablymeans______．

A.representativesinthePre-RaphaeliteMovement

B.peoplewhoareinfavorofFlorentine

C.criticswhoarelikelytomakeassessments

D.conservativesclingingtoclassicalart

35.

Fromthepassage,welearnthattheauthor

A.didn'tlikeRaoul'swayofdeliveringthepaper

B.didn'trealizewhyRaouldeliveredthepaperthatway

C.didn'tknowthatRaoulcameveryearlyinthemorning

D.didn'tfeelitnecessarytomeetRaoulwhenhecame

36.(68)

37.(75)

38.

TheGTE'sexampleshowsthat______.

A.efficienttechnologyiscost-effective

B.manymeetingsinacompanyareunnecessary

C.manypositionslikethatofatypistcanbedoneawaywith

D.itdoesn'tcostmuchtoautomatethefacilitiesofacompany

39.(78)

40.

Privacystandardsmadebyindividualstatesareineffectivebecause______.

A.thestandardsofdifferentstatescontradicteachother

B.onlinecommunicationisnotrestrictedtoanystate

C.thesestandardsignorethefederallawonthematter

D.thesestandardsareonlyapplicabletoregionalwebsites

四、閱讀理解(5題)41.

第

37

題

Whydoestheauthormentiongeneticengineeringandcomputerscience?

42.

根據(jù)下列選項(xiàng)回答41～45題：

第

41

題

1.__________

43.

第

39

題

canbeusedtoheatyourwaterathomeinsteadofsomuchgasorelectricity?__________

44.

第

49

題

hasthebestenginedesignintermsofsayingmoney?_________

45.

第

25

題

5.__________

參考答案

1.B

2.18.9%/18.9percent

3.Inhisoffice

4.B

5.A

6.B

7.Intreetrunk/Underneatharock．

8.A

9.C

10.A

11.D

12.C

13.B

14.Behavioralmanagement

15.B

16.happinesshappiness解析：根據(jù)上下文，日本年輕人更看重追求個(gè)人的幸福。所以此處應(yīng)填“happiness”。

17.sellingselling解析：關(guān)鍵是看and后面的buying。本句話(huà)的意思是“商家分析市場(chǎng)的供需情況?！惫蚀鸢笧閟elling。

18.butbut解析：此句意為“30歲的人表現(xiàn)出非常不同的握筆方式，…超過(guò)40歲的人都統(tǒng)一用三個(gè)手指握筆?！憋@然，此空處表轉(zhuǎn)折。

19.fromfrom解析：keepsth．fromdoingsth．意為“防止某事…”，為固定短語(yǔ)。

20.toto解析：“incontrastto”為固定搭配，意為“與…相對(duì)比”。所以此處應(yīng)填“to”。

21.dodo解析：解析見(jiàn)上題，為了避免與前面的know重復(fù)，這里可以換做do。故答案為do。

22.werewere解析：考查被動(dòng)語(yǔ)態(tài)的用法，注意分析句子成分。所以此處應(yīng)填“were”。

23.worseworse解析：“the+比較級(jí)，the+比較級(jí)”，意為“越…越…，”根據(jù)上下文，本句句意為“身邊的小玩意兒越多，事情似乎就會(huì)變得越糟糕?！彼源颂帒?yīng)填“worse”。

24.itit解析：本句意為“‘污染’意思是弄臟——表層土或什么東西，通過(guò)引進(jìn)雜質(zhì)，這使…不健康或不干凈?！憋@然，此空處應(yīng)指topsoilorsomething，因?yàn)榍懊嬉殉霈F(xiàn)，所以用it來(lái)代替。

25.someonesomeone解析：由本文的第一句話(huà)“‘Down-to-earth’meanssomeoneorsomethingthatishonest．realisticandeasytodealwith．”可知“Down-to-earth”指的是誠(chéng)實(shí)，現(xiàn)實(shí)、平易近人的那些人。這里的someone和后面是相對(duì)應(yīng)的。故答案為someone。

26.A解析：由A中的第一段“Thepopulationofthecityisabout800,000anditcoversanareaofover69squaremiles．”可知答案為A。

27.B解析：由第一段的“Insteadofbeseechingusalltogetvaccinated，they’renowurgingmosthealthypeoplebetweentheagesof2and64,notto．”可以判斷出美國(guó)之呼吁2至64歲的健康人不接種流感疫苗，而不是所有的美國(guó)人，因此答案A是錯(cuò)誤的。從第二段最后一句話(huà)可以看出疫苗生產(chǎn)廠(chǎng)家無(wú)法臨時(shí)增加疫苗生產(chǎn)不是由于他們不愿意，而是由于受精雞蛋的生產(chǎn)已經(jīng)預(yù)先計(jì)劃好，無(wú)法提供更多的受精雞蛋，由此可見(jiàn)答案C是錯(cuò)誤的。從第三段第三行“Fluvaccinesareharderthanmosttoproducethisway”可以判斷出答案D是錯(cuò)誤的，因?yàn)榱鞲幸呙绫葎e的疫苗更難用細(xì)菌培育的方式生產(chǎn)。而由第三段第2-3行“Themainchallengeistoshiftproductionfromeggsintocellcultures——amediumalreadyusedtomakemostothervaccines．”以及上一句可見(jiàn)，改造疫苗生產(chǎn)工藝的關(guān)鍵在于革新病毒培育技術(shù)。因此正確答案為B。

28.C解析：文中第一段提到“Butsuchbehavioralstudiescannotdistinguishbetweentwocompetingtheoriesofwhysleepisgoodforthe