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2021年甘肃省定西市公共英语五级(笔试)真题(含答案)学校:________班级:________姓名:________考号:________
一、1.ListeningComprehension(15题)1.PaulcouldreachalltheswitchesbecausetheyWereoriginallyinstalledattherightheightofhim.
A.RightB.Wrong
2.PartA
Directions:Youwillhearatalk.Asyoulisten,answerQuestions1-10bycirclingTRUEorFALSE.YouwillhearthetalkONLYONCE.Younowhave1minutetoreadQuestions1-10.
听力原文:Fromgoodreadingwecanobtainpleasure,companionship,experience,andinstruction.Agoodbookmayabsorbourattentionsocompletelythatforthetimebeingweforgetoursurroundingsandevenouridentity.Readinggoodbooksisoneofthegreatestpleasuresinlife.Itincreasesourcontentmentwhenwearecheerful,andlessensourtroubleswhenwearesad.Whatevermaybeourmainpurposeinreading,ourcontactwithgoodbooksshouldneverfailtogiveusenjoymentandsatisfaction.
Withagoodbookinourhandsweneedneverbelonely.Whetherthecharactersportrayedaretakenfromreallifeoraretotallyimaginarytheymaybecomeourcompanionsandfriends.Inthepagesofbookswecanwalkwiththewiseandthegoodofalllandsandalltimes.Thepeoplewemeetinbooksmaydelightuseitherbecausetheyresemblehumanfriendswhomweholddearorbecausetheypresentunfamiliartypeswhomwearegladtowelcomeasnewacquaintances.Ourhumanfriendssometimesmayboreus,butthefriendswemakeinbooksneedneverwearyuswiththeircompany.Byturningthepageswecandismissthemwithoutanyfearofhurtingtheirfeelings.Whenhumanfriendsdesertus,goodbooksarealwaysreadytogiveusfriendship,sympathy,andencouragement.
Oneofthemostvaluablegiftsbestowedbybooksisexperience.Fewofuscantravelfarfromhomeorhaveawiderangeofexperiences,butallofuscanleadvariedlivesthroughthepagesofbooks.Whetherwewishtoescapefromtheseeminglydullrealitiesofeverydaylifeorwhetherweexpecttovisitsomefar-offplace,abookwillhelpuswhennothingelsecan.Totravelbybookweneednobankaccounttopayourway;noairshiporoceanlinerorstream-linedtraintotransportus;nopassporttoenterthelandofourheart'sdesire.Throughbookswemaygetthethrillofhazardousadventurewithoutdanger.Wecanclimbloftymountains,bravetheperilsofanantarcticwinter,orcrossthescorchingsandsofthedesert,allwithouthardship.InbookswemayvisitthestudiosofHollywood;wemayminglewiththegaythrongsofmeParisboulevards;wemayjointhepicturesquepeasantsinanAlpinevillageorthekindlynativesonaSouthSeaisland.Indeed,throughbooksthewholeworldisoursfortheasking.Thepossibilitiesofourliteraryexperiencesarealmostunlimited.Thebeautiesofnature,theenjoymentofmusic,thetreasuresofart,thetriumphsofarchitecture,themarvelsofengineeringareallopentothewonderandenjoymentofthosewhoread.
Agoodbookmaydrawourattentionsocompletelythatweforgetoursurroundingsandevenouridentityforthetimebeing.
A.TrueB.Fasle
3.Whatsuggestiondoesthemanthinkitisgood?
A.Trytogiveupsmoking.
B.Eatsweetseverydayinsteadofsmoking.
C.Trytogiveuponecigaretteeveryday.
D.Gotoahypnotist.
4.Dr.WilsonasksWangtodoalittlemoreresearchbeforedecidingonhisproject.
A.RightB.Wrong
5.Thepossibilitiesofourliteraryexperiencesarealmostunlimited.
A.RightB.Wrong
6.Thedietsofthepeopleinthethreeregionsaretotallydifferent.
A.RightB.Wrong
7.Ifaconsumerwantsaquicksettlementoftheproblem,whomisitbettertocomplainto?
A.Ashopassistant.
B.Thestoremanager.
C.Themanufacturer.
D.Apublicorganization.
8.InwhichyeardidColumbustakechilipeppertoSpain?
9.PartA
Directions:Youwillhearatalk.Asyoulisten,answerQuestions1-10bycirclingTRUEorFALSE.YouwillhearthetalkONLYONCE.Younowhave1minutetoreadQuestions1-10.
听力原文:DoItYourselfMagazineorganizesacompetitioneverysummertoelectthe"Handymanoftheyear".ThewinnerofthisyearisMr.RoyMiller,aSheffieldpostman.Ajournalistandaphotographerhavecometohishouse.ThejournalistisinterviewingMr.Millerforanarticleinthemagazine.
W:Well,I'mveryimpressedbyalltheworkyou'vedoneonyourhouse,Mr.Miller.Howlonghaveyoubeenworkingonit?
M:IfirstbecameinterestedinDo-it-Yourselfseveralyearsago.Yousee,mysonPaulisdisabled.He'sinawheel-chairandIjusthadtomakealterationstothehouse.Icouldn'taffordtopayworkmentodoit.Ihadtolearntodoitmyself.
W:Hadyouhadanyexperienceinthiskindofwork?Didyouhaveanypracticalskills?
M:No.Igotafewbooksfromthelibrarybuttheydidn'thelpverymuch.SoIdecidedtogotoeveningclassessothatIcouldlearnbasiccarpentryandelectricalwiring.
W:Whatsortofchangesdidyoumaketothehouse?
M:Firstofall,practicalthingstohelpPaul.Youneverreallyrealizetheproblemshandicappedpeoplehaveuntilitattacksyourownfamily.Mostgovernmentbuildings,forexample,havestepsuptothedoor.Theydon'tplanbuildingssothatdisabledpeoplecangetinandout.Weusedtoliveinaflat,andofcourse,itwastotallyunsuitable.Justimaginetheproblemsadisabledpersonwouldhaveinyourhouse.WeneededalargernoisewithwidecorridorssothatPaulcouldgetfromoneroomtoanother.Wedidn'thavemuchmoneyandwehadtobuythisone.It'soverninetyyearsoldanditwasinaverybadstateofrepair.
W:Wheredidyoubegin?
M:Theelectrical.IcompletelyrewiredthehousesothatPaulcouldreachalltheswitches.Ihadtolowerthelightswitchesandraisethepower-points.IwentontodothewholehousesothatPaulcouldreachthingsandgowhereheneeded.
W:Whatelsedidyoudo?
M:BythetimeI'dalteredeverythingforPaul,do-it-yourselfhadbecomeahobby.Ireallyenjoyeddoingthingswithmyhands.Look,Ieveninstalledsmoke-alarms.
W:Whatwasthepurposeofthat?
M:Iwasveryworriedaboutfire.Yousee,Paulcan'tmoveveryfast.Ifittedthemsothatwewouldhaveplentyofwarningiftherewereafire.Iputinacompleteburglar-alarmsystem.Ittookweeks.Thefrontdooropensautomatically,andI'mgoingtoputadeviceonPaul'swheelchairsothathe'llbeabletoopenandcloseitwhenhewants.
W:Whatareyouworkingonnow?
M:I'vejustfinishedthekitchen.I'vedesigneditsothathecanreacheverything.NowI'mbuildinganextensionsothatPaulwillhavealargeroomonthegroundfloorwherehecanwork.
W:There'sa$10,000prize.Howareyougoingtospendit?
M:IamgoingtostartmyownbusinesssothatIcanconvertordinaryhousesfordisabledpeople.IthinkI'vebecomeanexpertondiesubject.
ThoughPaulisdisabled,hemanagedtomovearoundinthehouse.
A.TrueB.Fasle
10.Oneoftheadvantagesofchainschoolsisthattheyarefamousallovertheworld.
A.RightB.Wrong
11.听力原文: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
12.Peoplelikethechangesintheorganizationofthecompany.
A.TrueB.Fasle
13.What/Whoshouldstudentscontactiftheywanttogetasummerjob?
A.TheStudentUnion.
B.TheStudentEmploymentOffice.
C.TheWorkers'Union.
D.TheStudentPart-timeJobOffice.
14.PartB
Directions:Youwillhear3conversationsortalksandyoumustanswerthequestionsbychoosingA,B,CorD.YouwillheartherecordingONLYONCE.
听力原文:Doyoufindgettingupinthemorningdifficultandpainful?Thismightbecalledlaziness,butDr.Kleimanhasanewexplanation.Hehasprovedthateveryonehasadailyenergycycle.
Duringmehourswhenyoulaborthroughyourworkyoumaysaythatyou're"hot".That'strue.Thetimeofdaywhenyoufeelmostenergeticiswhenyourcycleofbodytemperatureisatitspeak.Forsomepeoplethepeakcomesduringtheforenoon.Forothersitcomesintheafternoonorevening.Noonehasdiscoveredwhythisisso.Thepossibleexplanationisthatoneisathistemperature-and-energypeakintheevening.Muchfamilyquarrelingendswhenhusbandsandwivesrealizewhattheseenergycyclesmean,andwhichcycleeachmemberofthefamilyhas.
Youcan'tchangeyourenergycycle,butyoucanlearntomakeyourlifefititbetter.Habitcanhelp,Dr.Kleimanbelieves.Maybeyou'resleepyintheeveningbutfeelyoumuststayuplateanyway.Counteractyourcycletosomeextentbyhabituallystayinguplaterthanyouwantto.Ifyourenergyislowinthemorningbutyouhaveanimportantjobtodoearlyintheday,risebeforeyourusualhour.Thiswon'tchangeyourcycle,butyou'llgetupandworkbetteratyourlowpoint.
Getofftoaslowstartwhichsavesyourenergy.Getupwithaleisurelyyawnandstretch.Sitontheedgeofthebedaminutebeforeputtingyourfeetonthefloor.Avoidthetroubleforcleanclothesbylayingthemoutthenightbefore.Wheneverpossible,doroutineworkintheafternoonandsavetasksrequiringmoreenergyorconcentrationforyoursharperhours.
Whatshouldonedoifhewantstoworkmoreefficientlyathislowpointinthemorning?
A.Changehisenergycycle.
B.Overcomehislaziness.
C.Getupearlierthanusual.
D.Gotobedearlier.
15.PartB
Directions:Youwillhear3conversationsortalksandyoumustanswerthequestionsbychoosingA,B,CorD.YouwillheartherecordingONLYONCE.
听力原文:W:Jim,thankgoodnessyou'vearrived.Theclasspresentationstartedhalfanhourago,andIwasjustbeginningtopanic.
M:I'msorryforbeinglate,Alice.Thismorninghasbeenarealmess.Ididn'tthinkIwasgoingtomakeithereatall.
W:Whyareyoulate?Ourpresentationdependsonthosegraphsyouareholding.
M:Yes,Iknow.I'lltellyouaboutitlater.First,let'sseehowwearedoingfortime.Twogroupsarestillaheadofus,aren'tthey?Thepresentationsonthefightsoftheconsumerandtheanalysisofthestockmarket.ThatmeansI'vegottwentyminutestosortout.
W:Youlookcold.Whathappened?
M:I'vebeenstandingoutsideinarctictemperaturesforoveranhourwaitingforabus.
W:Overanhour?ButIthoughtyourapartmentwasonlyatenminutebusridetocampus.
M:Innormalconditions,butthebuswasdelayedbecauseoftheweather,andwhenIstoppedinadrugstoretocallhomeforaride,thebuswentby.Asluckwouldhaveittherewasnooneathome,soIhadtowaitanotherforty-fiveminutesforthenextbus.
W:That'sMurphy'sLaw,isn'tit?Whatdiditsay?Ifanythingcangowrong,itwill.Well,we'vestillgottwentyminutestogetourwitstogether.
Whatisthewoman'stoneofvoicewhenshefirstseestheman?
A.Frustrated.B.Relieved.C.Sarcastic.D.Apologetic.
二、2.UseofEnglish(10题)16.
【C17】
17.
【C10】
18.
【C13】
19.(48)
20.(38)
21.(37)
22.
【C18】
23.(46)
24.(35)
25.(41)
三、3.ReadingComprehension(15题)26.PartB
Directions:Inthefollowingarticlesomeparagraphshavebeenremoved.ForQuestions66-70,choosethemostsuitableparagraphfromthelistA-Ftofitintoeachofthenumberedgaps.Thereisoneparagraphwhichdoesnotfitinanyofthegaps.MarkyouranswersonANSWERSHEET1.
Inthefollowingarticlesomeparagraphshavebeenremoved.ForQuestions66~70,choosethemostsuitableparagraphfromthelistA~Ftofitintoeachofthenumberedgaps.Thereisoneparagraphwhichdoesnotfitinanyofthegaps.MarkyouranswersonANSWERSHEET1.
DoesthepublisherofDouglasStarr'sexcellentBlood--AnEpicHistoryofMedicineandCommerceactuallyexpecttosellmanycopies?Whoeverchosethetitleiscertaintoscareoffthesqueamish,andthesubtitle,whichmakestheeffortsoundlikeadry,densesurveytext,hasreallydonethisbookadisservice.Infact,thebraveandcuriouswillenjoyabrightlywritten,intriguing,anddisquietingbook,withsomeimportantlessonsforpublichealth.
66.______
Thebookbeginswithahistoricalviewoncenturiesofloreaboutblood--inparticular,thebeliefthatbloodcarriedtheevilhumorsofdiseaseandrequiredoccasionaldraining.AsrecentlyastheRevolutionaryWar,bloodlettingwaswidelyappliedtotreatfevers.Theideaofusingoneperson'sbloodtohealanotherisonlyabout75yearsold—althoughroguescientistshadexperimentedwithtransfusinganimalbloodatleastasearlyasthe1600s.Thefirsttransfusionexperimentsinvolvedstitchingadonor'svein(inearlycasesthephysician's)toapatient'svein.
67.______
Sabotagedbynotionsaboutthe"purity"oftheirgroups'blood,JapanandGermanylaggedwellbehindtheAlliesintransfusionscience.OncetheyrealizedtheywerelosinginjuredtroopstheAllieshadlearnedtosave,theytriedtocatchup,conductinghorribleandunproductiveexperimentssuchasdrainingbloodfromPOWsandinjectingthemwithhorsebloodorpolymers.
68.______
Duringtheearlytomid-1980s,Startsays,10,000Americanhemophiliacsand12,000otherscontractedHIVfromtransfusionsandreceiptofbloodproducts.Bloodbanksbothhereandabroadmovedslowlytoacknowledgethethreatofthevirusandinsomecasesevenactedwithcriminalnegligence,allowingthedistributionofbloodtheyknewwastainted.Thisisnotnewmaterial.ButStarr'sinsightsaddadimensiontoastoryfirstexploredinthelateRandyShilts'sAndtheBondPlayedOn.
69.______
Isthebloodsupplysafenow?Screeningproceduresandtechnologyhavegottenmuchmoreadvanced.Yetit'sdisturbingtoreadStarr'scontentionthatapersonreceivingmultipletransfusionstodayhasaboutalin90,000chanceofcontractingHIV--farhigherthanthe"oneinamillion"figurethatbloodbankersonceblithelyandfalselyquoted.Moreover,newpathogensthreatentoemergeandspreadthroughtheincreasinglyhigh-speed,globalblood-productnetworkfasterthansciencecanstopthem.ThispromptsStarttoarguethattoday'sbloodstoresare"simultaneouslysaferandmorethreatening"thanwhendistributionwaslesssophisticated.
70.______
A.Themassivewartimeblooddriveslaidthegroundworkformodernblood-banking,whichhassavedcountlesslives.Unfortunately,thesedevelopmentsalsosetthestageforagreatmoderntragedy--thespreadofAIDSthroughtheinternationalbloodsupply.
B.Thereissomuchdrama,power,resonance,andimportantinformationinthisbookthatitwouldbeashameifthesqueamishwerescaredoff.Perhapsthekeylessonisthis:Thepublichealthmustalwaysbeguardedagainstthepressuresandpitfallsofcompetitivemarketsandhumanfallibility.
C.Inhischronicleofaresource,Startcoversanenormousamountofground.Hegivesusanaccountofmankind'sattitudesovera400-yearperiodtowards
27.(69)
28.(68)
29.TheVillageGreeninNewMilford,Connecticut,isasnapshotofNewEnglandcharm:acarefullymanicuredlawnflandedbyscrupulouslymaintainedcolonialhomes.Babysittersdandlekidsinthewoodengazebo,waitingforcommuterparentstoreturnfromNewYork.OnalazyafternoonlastweekCarolineNicholas,16,hadnothingmorepressingtodothandrinkintheearly-summersunshineanddiscusstherecenteventsintown.“Idon'tthinkalotofolderpeopleknewtherewereunhappykidsinNewMilford,”shesaid,“Icouldseeitcoming.”
Inafive-dayperiodinearlyJuneeightgirlswerebroughttoNewMilfordHospitalafterwhathospitalofficialscallsuicidalgestures.Thegirls,allbetween12and17,triedavarietyofmeasures,includingheavydosesofalcohol.over-the-countermedicinesandcutsorscratchestotheirwrists.Nonewassuccessful,andmostdidn'trequirehospitalization;butatleasttwoattempts,accordingtothehospital,couldhavebeenvital.Theirreasonsseemedasmundaneastheotherhappen-stancesofsuburbanlife.“Iwasjustsickofitall,”onetoldareporter,“Everythinginlife.”Mostalarming,emergency-roomdoctorFrederickLohsetoldalocalreporterthatseveralgirlssaidtheywerepartofasuicidepact.Thehospitallaterbackedawayfromthisremark.Butcominginthewakeofatleastsixteensuicideattemptsoverthepreviousfewmonths.thissuddencluster—alongwiththeinfluxofmedia—hassetthiswell-groomedsuburbof23,000onedge.AtatownmeetinglastWednesdaynight,DrSimonSobo,chiefofpsychiatryatthehospital,toldmorethan200parentsandkids,“We'retalkingaboutacrisisthathasreallygottenoutofhand.”Laterheadded,“TherehavebeenmoresuicideattemptsthisspringthanIhaveseeninthe13yearsIhavebeenhere.”
Sobosaidthatthegirlshetreateddidn'thaveseriousproblemsathomeorschool.“Manyofthesewerepopularkids,”hesaid,“Theygotplentyoflove,butbeneaththereassuringsigns,aswathofteensherearenotmakingit.”Somesaythatdrugs,bothpotand‘realdrugs’,arecommonplace.KidshaveshownupwithLIFESUCKSandLONGLIVEDEATHpennedontheirarms.Afewgirlscasuallydisplayscarsontheirarmswheretheycutthemselves.“You'dbesurprisedhowmanykidstrysuicide,”saidonegirl,17.“Youdon'twanttoputpainonotherpeople;youputitonyourself.”Shesaidsheusedtocutherself“justtoreleasethepain”.
Emily,15,afriendofthreeofthegirlstreatedin,June,saidonewashavingfamilyproblems,onewas“upsetthatday”andthethirdwas“justupsetwitheverythingelsegoingon”.Shesaidtheyweren'treallytryingtokillthemselves—theyjustneededconcern.AsSobonoted,“What'sgoingoninNewMilfordisnotuniquetoNewMilford.”Thesameunderlyingcultureofdespaircouldbefoundinanytown.Butteensuicide,headded,canbea“contagion”.RightnowNewMilfordhasthebug-andhasitbad.
Whatisthemainsubjectofthepassage?
A.EightgirlscommittedsuicideinNewMilford.
B.ThevillageGreenisnotacharmingplace.
C.Teenagersuicide.
D.Dr.SimonSobo'sachievements.
30.
Whichofthefollowingstatementsistrueaboutinsuranceproducts?
A.Peoplehavenochoicewhenbuyinginsuranceproducts.
B.Thereweresomanychoicesininsuranceproductsinthepastthatpeoplefounditdifficulttomakeadecision.
C.Therearenobetterandcheaperinsuranceproducts.
D.Itisbetterforpeopletohavesomanyinsuranceproductstochoose.
31.
______mayaffectthedownstreamwaterqualityandhaveanimpactonplantlife?
32.(70)
33.(73)
34.PartB
Directions:Inthefollowingarticlesomeparagraphshavebeenremoved.ForQuestions66-70,choosethemostsuitableparagraphfromthelistA-Ftofitintoeachofthenumberedgaps.Thereisoneparagraphwhichdoesnotfitinanyofthegaps.MarkyouranswersonANSWERSHEET1.
Periodicallyinhistory,therecomeperiodsofgreattransitioninwhichworkchangesitsmeaning.Therewasatime,perhaps10,000yearsago,whenhumanbeingsstoppedfeedingthemselvesbyhuntinggameandgatheringplants,andincreasinglyturnedtoagriculture.Inaway,thatrepresentedtheinventionof"work".
Then,inthelatterdecadesofthe18thcentury,astheIndustrialRevolutionbeganinGreatBritain,therewasanothertransitioninwhichthesymbolsofworkwerenolongerthehoeandtheplow;theywerereplacedbythemillandtheassemblyline.
66.______
WiththeIndustrialRevolution,machinery—poweredfirstbysteam,thenbyelectricityandinternalcombustionengines—tookoverthehardphysicaltasksandrelievedthestrainonhumanandanimalmuscles.
67.______
Andyet,suchjobshavebeencharacteristicofthehumanconditioninthefirstthree-quartersofthe20thcentury.They'vemadetoolittledemandonthehumanmindandspirittokeepthemfreshandalive,madetoomuchdemandforanymachinetoservethepurposeuntilnow.
Theelectroniccomputer,inventedinthe1940'sandimprovedatbreakneckspeed,wasamachinethat,forthefirsttime,seemedcapableofdoingworkthathaduntilmenbeenthepreserveofthehumanmind.Withthecomingofthemicrochipinthe1970's,computersbecamecompactenough,versatileenoughand(mostimportantofall)cheapenoughtoserveasthebrainsofaffordablemachinesthatcouldtaketheirplaceontheassemblylineandintheoffice.
68.______
First,whatwillhappentothehumanbeingswhohavebeenworkingatthesedisappearingjobs?Second,wherewillwegetthehumanbeingsthatwilldothenewjobsthatwillappear—jobsthataredemanding,interestingandmind-exercising,butthatrequiresahigh-techlevelofthoughtandeducation?
69.______
Thefirstproblem,thatoftechnologicalunemployment,willbetemporary,foritwillariseoutofthefactthatthereisnowagenerationofemployeeswhohavenotbeeneducatedtofitthecomputerage.However,(inadvancednations,atleast)theywillbethelastgenerationtobesolacking,sothatwiththemthisproblemwilldisappearor,atleast,diminishtothepointofnon-crisisproportions.
Thesecondproblem—thatofdevelopingalargeenoughnumberofhigh-techmindstorunahigh-techworld—willbenoproblematall,onceweadjustourthinking.
70.______
Rightnow,creativityseemstobeconfinedtoaveryfew,anditiseasytosupposethatthatisthewayitmustbe.However,withtheproperavailabilityofcomputerizededucation,humanitywillsurprisetheelitefewonceagain.
A.Thereremained,however,the"easier"labor—thelaborthatrequiredthehumaneyes,ears,judgmentandmindbutnosweating.Itneverthelesshaditsmiseries,forittendedtobedull,repetitious,andboring.Andthereisalwaysthesoursenseofendlesslydoingsomethingunpleasantundercompulsion.
B.Foronething,muchofhumaneffortthatistodayputinto"runningtheworld"willbeunnecessary.Withcomputers,robotsandautomation,agreatdealofthedailygrindwillappeartoberunningitself.Thisisnothingstartling.ItisatrendthathasbeenrapidlyonitswayeversinceWorldWarII.
C.Andnowwestandatthebrinkofachangethatwillbethegreatestofall,forworkinitsoldsensewilldisappearaltogether.Tomostpeople,workhasalwaysbeenaneffortfulexercisingofmindorbody—compelledbythebitternecessityofearningthenecessitiesoflife—plusanoc
35.Theideaofafishbeingabletoproduceelectricitystrongenoughtolightlampbulbs-oreventorunasmallelectricmotor—isalmostunbelievable,butseveralkindsoffishareabletodothis.Evenmorestrangely,thiscuriouspowerhasbeenacquiredindifferentwaysbyfishbelongingtoverydifferentfamilies.
Perhapsthemostknownaretheelectricrays,ortorpedoes,ofwhichseveralkindsliveinwarmseas.Theypossessoneachsideofthehead,behindtheeyes,alargeorganconsistingofanumberofhexagonal-shapedcellsratherlikeahoneycomb.Theceilsarefilledwithajelly-likesubstance,andcontainaseriesofflatelectricplates.Oneside,thenegativeside,ofeachplate,issuppliedwithveryfinenerves,connectedwithamainnervecomingfromaspecialpartofthebrain.Currentgetsthroughfromtheupper,positivesideoftheorgandownwardtothenegative,lowerside.Generallyitisnecessarytotouchthefishintwoplaces,completingthecircuit,inordertoreceiveashock.
Thestrengthofthisshockdependsonthesizeoffish,butnewly-bornonesonlyabout5centimetersacrosscanbemadetolightthebulbofapocketflashlightforafewmoments,whileafullygrowntorpedogivesashockcapableofknockingamandown,and,ifsuitablewiresareconnected,willoperateasmallelectricmotorforseveralminutes.
Anotherfamousexampleistheelectriceel.Thisfishgivesanevenmorepowerfulshock.Thesystemisdifferentfromthatofthetorpedointhattheelectricplatesrunlongitudinallyandaresuppliedwithnervesfromthespinalcord.Consequently,thecurrentpassesalongthefishfromheadtotail.Theelectricorgansofthesefisharereallyalteredmusclesandlikeallmusclesareapttotire,sotheyarenotabletogenerateelectricityforverylong.PeopleinsomepartsofSouthAmericawhovaluetheelectriceelasfood,takeadvantageofthisfactbydrivinghorsesintothewateragainstwhichthefishdischargetheirelectricity.Thehorsesarelessaffectedthanamanwouldbe,andwhentheelectriceelshaveexhaustedthemselves,theycanbecaughtwithoutdanger.
TheelectriccatfishoftheNileandofotherAfricanfreshwatershasadifferentsystemagainbywhichcurrentpassesoverthewholebodyfromthetailtothehead.Theshockgivenbythisarrangementisnotsostrongastheothertwo,butisnonethelessunpleasant.Theelectriccatfishisaslow,lazyfish,fondofgloomyplacesandgrowstoabout1metrelong;itiseatenbytheArabsinsomeareas.
Thepowerofproducingelectricitymayservethesefishbothfordefenceandattack.Ifalargeenemyattacks,theshockwilldriveitaway;butitappearsthatthecatfishandtheelectriceelusetheircurrentmostoftenagainstsmallerfish,stunningthemsothattheycaneasilybeoverpowered.
Whichofthefollowingcanproducethestrongestshock?
A.The
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