小学、初中、高中各种试卷真题知识归纳文案合同PPT等免费下载www.doc985.com小学、初中、高中各种试卷真题知识归纳文案合同PPT等免费下载www.doc985.com选择性必修第三册Unit3BacktothepastⅠ.阅读理解A(2024·江泰州苏调研)ThecommonlyheldviewisthatpeoplearrivedinNorthAmericafromAsiaviaalandbridgeonceconnectingthetwocontinents.Butrecentdiscoverieshavesuggestedhumansmighthavebeenthereearlier.ResearchersstudyingfossilizedhumanfootprintsinNewMexicosaythathumanswerethereatleast23,000yearsago.MatthewBennett，aspecialistinancientfootprintsandauthorofastudyonthenewfindingspublishedinScience，andhiscolleaguesstudied61footprintsbyradiocarbondatinglayersofaquatic(水生的)plantseedspreservedaboveandbelowthefootprintsandaccuratelydatedtheyweremade21,000to23,000yearsago.ThepeoplewhomadethefootprintswerelivingthereinthelastIceAgewhentwomassiveicesheetscoveringthecontinentandcoldtemperatureswouldhavemadeajourneybetweenAsiaandAlaskaimpossible，indicatinghumansmusthavebeentheremuchearlierthanpreviouslythought.Accordingtotheiranalysisofthefootprints，theywerelikelymadeinsoftgroundattheedgeofawetlandbychildrenwhoweresenttodotheworklikefetchingandcatchingbyadults.Windprobablyblewdustoverthesurface，accumulatingintheprints，thus，leavingfootprintsthatpreviouslyrecorded.Theirfindingalsomakesitpossibletoexploretheolderandmorecontroversialsiteswithadifferentlight.OnesuchsiteisChiquihuiteCaveincentralMexico，wherestonetoolsdatingbackto30,000yearsagohavebeenfound.DavidRachal，anuninvolvedbutexperiencedgeoarchaeologist(地质考古学家)thoughtthefootprintdatesprovidedbyBennettandhisteamlooked“solid”，withseedsprovidingveryreliableandpreciseagesthroughradiocarbondating.“Youcouldnotaskforabettersetup，”saidRachal.However，hewaspuzzledthatnoartifacts，suchasstonetools，hadbeenfoundinthearea.Hethoughtitwasjustathemethatwasgainingsomeserioustractionintheliterature.1．Whatisthemostessentialevidencedatingthetimeinthepassage?A．Theaquaticplantseeds.B．Thefossilizedhumanfootprints.C．Theunearthedtools.D．Themassiveicesheets.2．WhydoestheauthormentionChiquihuiteCaveincentralMexico?A．Tointroduceahistoricalsite.小学、初中、高中各种试卷真题知识归纳文案合同PPT等免费下载www.doc985.com小学、初中、高中各种试卷真题知识归纳文案合同PPT等免费下载www.doc985.comB．Toshowthesignificanceofthefootprints.C．Tocomparegeoarchaeologicaldiscoveries.D．Toexplainthecourseofmakingadiscovery.3．What’sDavidRachal’sattitudetowardsthenewdiscovery?A．Optimisticandtrustful.B．Conservativeandcautious.C．Negativebutcurious.D．Favorablebutconfused.4．Whatisthepassagemainlyabout?A．Thediscoveryofhumanfootprints.B．Scientificmethodsofdatingfootprints.C．TheearlierarrivalofpeopleinNorthAmerica.D．Adiscussiononhumanhistoryamongresearchers.BAstrongsenseofsmellisakeycomponentofahealthyandenjoyablelife.Yetoursenseofsmellisindeclineasaresultofanunnoticedthreattoourhealth：airpollution.Scientistsarefindingthatanosmia，alossofthesenseofsmell，isbecomingawidespreadproblemamongpeopleofallagesexposedtoPM2.5pollutantsconstantly，whicharetinyparticles(微粒)thatcanenterourbodieswitheverybreathwetake.Thereason，theysuggest，isthattheolfactorybulbs(嗅球)，whicharelocatedinournosesandpackedwithnerveendings，areaffectedbyexposuretoairpollution.Thetinyparticlescauseillnesseitherinthebulbsthemselvesorinthebrain，impactingoursenseofsmellovertime，“Ourdatashowtheriskofdevelo...