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一阅读PassageOneSomedesertanimalscansurvivethesummerheatanddrynessbecausetheyareveryunusual.Thecamel,forexample,canexperienceandbearanincreaseinthetemperatureofitsbodyanditsbloodof9℃withoutanythingbadhappeningtoit.Inaddition,itcandrinkalotofwateratonetime;thenstoreenoughwaterinpartsofitsbodytosupplyitsneedsfortwoweeksormore.Thekangaroorat,ontheotherhand,getsallthewateritneedsfromwaterthatitproduceswhenitbreathes.However,mostanimalsneedtomaintainafairlyconstantbodytemperature,andwilldieifitrisesmorethan5℃.Therefore,theyneedtofindsomewaytostayawayfromtheheatofthesummersun.Norcanmanyanimalseitherstoreorproducewaterintheirbodies,asthecamelandkangarooratcan.Sotheymustfindwaystokeeptheirbodiesfromlosingwaterbecauseoftheheat.Becauseveryfewdesertanimalscansurvivethehightemperatureofatypicalsummer’sday,mostofthemareactiveonlyinthenight.Onlyafterthesunhassetdoesthedesertcomefullytolife.Thenightisrelativelycool,andthedarknessprovidesprotection,notonlyfromthesun,butalsofromotheranimalsandfromthebirds.Sothecomingofdarknessisthesignalforthelargemajorityofanimalsandinsectstostartagaintheirsearchforwaterandfood.Whenmorningcomes,mostofthemseekshelteragain:manygounderground;nearlyallfindsomedarkandcoolplacewheretheycankeepawayfromthesun’sheat.Formanyspeciesofinsects,livinginthedesertiseasierthanforanimals.Likemanydesertplants,theyhaveawaterproofskinwhichpreventswaterlossbecauseofthehightemperature.Inaddition,somespeciesspendallormostoftheirlifebelowground.Here,formostoftheyearatleast,thereissomemoisture,anditisgenerallycoolerthanonthesurface.Inthecaseofants,onlyadultsleavetheundergroundnests,andtheydosoonlytogatherfoodortodefendthenestagainstattack.26.Comparedwithotherdesertanimals,thecamelcanbear.A.averylowbodytemperatureB.onlyalittlechangeinbodytemperatureC.abigincreaseinbodytemperatureD.aconstantchangeinbodytemperature27.Thekangarooratisdifferentfromotheranimalsinthat.A.itcanproducewaterthroughbreathingB.itcanstorewaterinpartsofitsbodyC.itcanmaintaindifferentbodytemperatureD.itcandrinkalotofwateratatime28.Whyisthedesertfullofactivityinsummernights?A.Becauseitiscoolerandsaferformostanimals.B.Becauseanimalscanfindfoodinthedark.C.Becauseitiseasytofindwateratnight.D.Becauseanimalscannotsleepatnight.29.Whyisiteasyformanyspeciesofinsectstoliveinthedesert?A.Becauseitisnotdifficultforthemtosurvivethere.B.Becausetheyarenotafraidoftheheat.C.Becauseitisnotdifficultforthemtofindfoodthere.D.Becausetheyhaveawaterproofskin.30.Mostinsectslivebelowthegroundbecause.A.itiseasyforthemtobuildneststhereB.itiseasytofindwaterthereC.itiscoolertherethanonthesurfaceD.itiseasiertodefendtheirnestsPassagetwoCarsareanimportantpartoflifeintheUnitedStates.Withoutacarmostpeoplefeelthattheyarepoor.Anevenifapersonispoorhedoesn’tfeelreallypoorwhenhehasacar.HenryFordwasthemanwhofirststartedmakingcarsinlargenumbers.Heprobablydidn’tknowhowmuchthecarwasgoingtoaffectAmericanculture.ThecarmadetheUniteStatesanationonwheels.AndithelpedmaketheUnitedStateswhatitistoday.TherearethreemainreasonsthecarbecamesopopularintheUnitedStates.Firstofall,thecountryisahugeoneandAmericansliketomovearoundinit.Thecarprovidesthemostcomfortableandcheapestformoftransportation.Withacarpeoplecangoanyplacewithoutspendingalotofmoney.ThesecondreasoncarsarepopularisthefactthattheUnitedStatesneverreallydevelopedanefficientandinexpensiveformofpublictransportation.Long-distancetrainshaveneverbeenascommonintheUnitedStatesastheyareinotherpartsoftheworld.Nowadays,thereisagoodsystemofair-serviceprovidedbyplanes.Butitistooexpensivetobeusedfrequently.Thethirdreasonisthemostimportantone,though.TheAmericanspiritofindependenceiswhatreallymadecarspopular.Americansdon’tliketowaitforabusoratrainorevenaplane.Theydon’tliketohavetofollowanexactschedule.Acargivesthemthefreedomtoscheduletheirowntime.AndthisisthefreedomthatAmericanswantmosttohave.ThegasshortagehascausedabigproblemforAmericans.Buttheanswerwillnotbeabiggersystemofpublictransportation.Therealsolutionwillhavetobeanewkindofcar,onethatdoesnotusesomuchgas.31.WhendomostAmericansfeeltheyarepoor?A.Whentheydon’thaveacar.B.Whentheyliveinahugecountry.C.Whentheydon’tuseplanes.D.Whentheyhaveacar.32.WhydocarsbecomepopularintheUnitedStates?A.TheUnitedStatesishuge.B.Publictransportationisnotsogood.C.Americansliketobeindependent.D.Americansliketomovearound.33.WhatpublictransportationisgoodintheUnitedStates?A.Buses.B.Trains.C.Taxis.D.Planes34.WhathascausedabigproblemforAmericans?A.Anewkindofcar.B.Publictransportation.C.Thegasshortage.D.Poorpeople.35.Whichofthefollowingisnotmentionedaccordingtothispassage?A.Carshavemadethenationonwheels.B.CarshavemadetheUnitedStateshaveagasshortage.C.Nearly80%oftheAmericanpeoplehavecars.D.CarshavemadeAmericansindependent.PassagethreeEversinceIwasverysmall,I’vehadthesensethatIoughttobesomewhereelse.IrememberwatchingtrainsflashbyandwishingIwasonboard.IremembergoingtotheairportwithmyparentswhenIwas13andreadingthedestinationsboard,seeingalltheplacesthatIcouldgoto:LosAngeles,Chicago,London.Butthetrainpassedbyandplanestookoffwithoutme,soIwande