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1、1996年10月托福阅读全真试题1996年10月托福阅读全真试题Question1-8WhenJulesVernewroteJourneytotheCenteroftheEarthin1864,thereweremanyconflictingtheoriesaboutthenatureoftheEarth'sinterior.Somegeologiststhoughtthatitcontainedahighlycompressedballofincandescentgas,whileotherssuspectedthatitconsistedofse
2、parateshells,eachmadeofadifferentmaterial.Today,welloveracenturylater,thereisstilllittledirectevidenceofwhatliesbeneathourfeet.MostofourknowledgeoftheEarth'sinteriorcomesnotfromminesorboreholes,butfromthestudyofseismicwaves-powerfulpulsesofenergyreleasedbyearthquakes.Thewaythat
3、seismicwavestravelshowsthattheEarth'sinteriorisfarfromuniform.Thecontinentsandtheseabedareformedbythecrust-athinsphereofrelativelylight,solidrock.Beneaththecrustliesthemantle,averydifferentlayerthatextendsapproximatelyhalfwaytotheEarth'scenter.Theretherockisthesubjectofabattleb
4、etweenincreasingheatandgrowingpressure.Initshighlevels,themantleisrelativelycool;Atgreaterdepths,hightemperaturesmaketherockbehavemorelikealiquidthanasolid.Deeperstill,thepressureisevenmoreintense,preventingtherockfrommeltinginspiteofahighertemperature.Beyondadepthofaround2,900
5、kilometers,agreatchangetakesplaceandthemantlegiveswaytothecore.Someseismicwavescannotpassthroughthecoreandothersarebentbyit.Fromthisandotherevidence,geologistsconcludethattheoutercoreisprobablyliquid,withasolidcenter.Itisalmostcertainlymadeofiron,mixedwithsmalleramountsofothere
6、lementssuchasnickel.TheconditionsintheEarth'scoremakeitafarmorealienworldthanspace.Itssolidironheartissubjectedtounimaginablepressureandhasatemperatureofabout9,000oF.Althoughscientistscanspeculateaboutitsnature,neitherhumansnormachineswilleverbeabletovisitit.1.Theword"conflicti
7、ng"inline2isclosestinmeaningto(A)controlling(B)outdated(C)opposing(D)important2.Whatistoday'srichestsourceofinformationabouttheEarth'sinteriorforgeologists?(A)Boreholes(B)Shells(C)Seismicwaves(D)Mines3.Theword"There"inline16referstothe(A)mantle(B)crust(C)seabed(D)Earth'scenter.
8、4.WhichofthefollowingisaprimarycharacteristicoftheEart