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英语六级阅读备考练习题及答案 无论是在学校还是在社会中,我们会经常接触并使用练习题,做习题在我们的学习中占有非常重要的位置,对掌握知识、培养能力和检验学习的效果都是非常必要的,还在为找参考习题而苦恼吗?下面是小编精心整理的英语六级阅读备考练习题及答案,仅供参考,大家一起来看看吧。英语六级阅读备考练习题及答案1Thelifestoryofthehumanspeciesgoesbackamillionyears,andthereisnodoubtthatmancameonlyrecentlytothewesternhemisphere.NoneofthethousandsofsitesofaboriginalhabitationuncoveredinNorthandSouthAmericahasantiquitycomparabletothatofoldWorldsites.Man‘soccupationoftheNewWorldmaydateseveraltensofthousandsofyears,butnoonerationallyarguesthathehasbeenhereeven100,000years.SpeculationastohowmanfoundhiswaytoAmericawaslivelyattheoutset,andtheproposedroutesboxedthecompass.Withoneortwonotableexceptions,however,studentsofAmericananthropologysoonsettledfortheplausibleideathatthefirstimmigrantscamebwayofalandbridgethathadconnectedthenortheastcomerofAsiatothenorthwestcornerofNorthAmericaacrosstheBeringStrait.Marinerswereabletosupplythereassuringinformationthatthestraitisnotonlynarrow–itis56mileswide–butalsoshallow,aloweringofthesealevelthereby100feetorsowouldtransformthestraitintoanisthmus(地峡).WithlittleeelsinthewayofevidencetosustaintheBeringStraitlandbridge,anthropologists(人类学家)embracedtheideathatmanwalkeddryshod(不湿鞋的)fromAsiatoAmerica.Towardtheendofthelastcentury,however,itbecameapparentthattheWesternHemispherewastheNewWorldnotonlyformanbutalsoforahostofanimalsandplants.ZoologistsandbotanistsshowedthatnumeroussubjectsoftheirrespectivekingdomsmusthaveoriginatedinAsiaandspreadtoAmerica.Thesefindingswereneitherastonishingnorwhollyunexpected.Suchspreadofpopulationsisnottobeenvisionedasanexodusormassmigration,eveninthecaseofanimals.Itis,rather,aspillingintonewterritorythataccompaniesincreaseinnumbers,withmovementinthedirectionofleastpopulationpressureandmostfavorableecologicalconditions.Buttheimmensetrafficinplantandanimal‘sformsplacedaheavyburdenontheBeringStraitlandbridgeastheanthropologistsaheadenvisionedit.Whereaspurposefulmencouldmaketheirwayacrossanarrowbridge,theslowdiffusionofplantandanimalswouldrequireanavenueasacontinentandavaila