TOEFL试题12.docx

TOEFL试题12.docx

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TOEFL试题12

TOEFL试题

（1）2

11.Theword"durable"'inhue3isclosestinmeaningto

（A）lasting

（B）delicate

（C）heavy

（D）Plain

12.Whatdoestheauthorimplyabouttherawmaterialsusedtomakeglass?

（A）Theywerethesameforcenturies.

（B）Theyarcliquid

（C）Theyaretransparent

（D）Theyareveryheavy.

13.Accordingtothepassage,howisglassthathascooledandbecomerigiddifferentfrommostotherrigidsubstances?

（A）Ithasaninterlockingcrystalnetwork.

（B）Ithasanunusuallylowmeltingtemperature.

（C）Ithasvaryingphysicalproperties.

（D）Ithasarandommolecularstructure.

14.Theword"customarily"inline13isclosestinmeaningto

（A）naturally

（B）necessarily

（C）usually

（D）certainly

15.Thewords"exposedto"inline19areclosestinmeaningto

（A）hardenedby

（B）chilledwith

（C）subjectedto

（D）deprivedof

16.Whatmustbedonetoreleasetheinternalstressesthatbuildupinglassproductsduringmanufacture?

（A）theglassmustbereheatedandevenlycooled.

（B）theglassmustbecooledquickly.

（C）Theglassmustbekeptmoistuntilcooled.

（D）Theglassmustbeshapedtoitsdesiredformimmediately

17.Theword"induced"inline21isclosestinmeaningto

（A）joined

（B）missed

（C）caused

（D）lost

18.Theword"it"inline22refersto

（A）feature

（B）glass

（C）manner

（D）viscosity

19.Accordingtothepassage.whycanglassbemoreeasilyshapedintospecificformsthancanmetals

（A）Itresistsbreakingwhenheated

（B）Ithasbetteropticalproperties.

（C）Itretainsheatwhileitsviscositychanges.

（D）Itgraduallybecomessofterasitstemperaturerises.

Question20-30

Agreatdealcanbelearnedfromtheactualtracesofancienthumanlocomotion:

thefootprintsofearlyhominids.Thebest-knownspecimensaretheremarkabletracksdiscoveredatLactoli,Tanzania,byMaryLeaky.Thesewereleftbysmallhominidsaround3.6to3.75millionyearsago,accordingtopotassium–argondatesofthevolcanicrocksaboveandbelowthislevel.Thesehominidswalkedacrossastretchofmoistvolcanicash,whichwassubsequentlyturnedtomudbyrain,andwhichthensetlikeconcrete.

ExaminationofheshapeoftheprintsrevealedtoMaryLeakeythatthefeethadaraisedarch,aroundedheel,apronouncedball,andabigtoethatpointedforward.Thesefeatures,togetherwiththeweight-bearingpressurepatterns,resembledtheprintsofupright-walkingmodernhumans.Thepressuresexertedalongthefoot,togetherwiththelengthofstride,whichaveraged87centimeters,indicatedthatthehominidshadbeenwalkingslowly.Inshort,allthedetectablemorphologicalfeaturesimpliedthatthefeetthatleftthefootprintswereverylittledifferentfromthoseofcontemporaryhumans.

Adetailedstudyhasbeenmadeoftheprintsusingphotogrammetry,atechniqueforobtainingmeasurementsthroughphotographs,whichcreatedadrawingshowingallthecurvesandcontoursoftheprints.Theresultemphasizedthattherewereatleastsevenpointsofsimilaritywithmodernbipedalprints,suchasthedepthoftheheelimpression,andthedeepimprintofthebigtoe.MDayandE.WickensalsotookstereophotographsoftheLactoliprintsandcomparedthemwithmodernprintsmakebymenandwomeninsimilarsoilconditions.Onceagain,theresultsfurnishedpossibleevidenceofbipedalism.Footprintsthusprovideusnotmerelywithrareimpressionsofthesofttissueofearlyhominids,butalsowithevidenceofuprightwalingthatinmanywaysisclearerthancanbeobtainedfromtheanalysisofbones.

Thestudyoffossilfootprintsisnotrestrictedtoexamplesfromsuchremoteperiods.Hundredsofprintsareknown,forexample,inFrenchcavesdatingfromtheendofthelasticesage,approximately10,000yearsago.ResearchbyLeonPales,usingdetailedsiliconresinmoldsoffootprintsmostlymadebybarefeet,hasprovidedinformationaboutthisperiod.

20.Whatdoesthepassagemainlydiscuss?

（A）Theanalysisoffootprintfossils

（B）Accuratedatingofhominidremains

（C）thecareerofMaryLeakey

（D）Behavioralpatternsofearlyhumans

21.Theword"remarkable"inline2isclosestinmeaningto

（A）extraordinary

（B）enormous

（C）various

（D）orderly

22.TheageoftheLaetolifootprintswasestimatedby

（A）testingthefossilizedbonesofthehominids

（B）studyingtheshapeofthefootprints

（C）analyzingnearlyrocklayers

（D）comparisonwithfootprintsfromotherlocations

23.ItcanbeinferredthatthefootprintsinvolcanicashatLaetoliwerewellpreservedbecause

（A）theywereburiedbyasecondvolcaniceruption

（B）theashcontainedpotassiumantiargon

（C）theashwasstillwarmfromthevolcaniccruptions

（D）suitableconditionscausedtheash10harden

24.WhichorthefollowingisNOTmentionedasacharacteristicofthefeetinMaryLeakey'sfossilfind?

（A）Theshapeortheheel

（B）Thenumberoftoes

（C）Araisedarch

（D）Apronouncedball

25.Theword"exerted"inline11isclosestinmeaningto

（A）influenced

（B）applied

（C）returned

（D）lessened

26.Thefigureof87centimetersmentionedinline12referstothesizeofthe

（A）objectscarriedbythehominids

（B）stepstakenbythehominids

（C）hominidsbodies

（D）hominidsfeet

27.Whydoestheauthormentionthe"heelimpression"inline19?

（A）Toemphasizethesizeofthehominidsfoot

（B）Tospeculateonapossibleinjurythehominidhadsuffered

（C）Togiveanexampleofsimilaritytomodernhumanfootprints

（D）Toindicatetheweightofearlyhominids

28.Theword"restricted"inline26isclosestinmeaningto

（A）limited

（B）improved

（C）continued

（D）succeeded

29.WhatcanbeinferredaboutthefootprintsfoundinFrenchcavesmentionedinthelastparagraph?

（A）TheyshowmoredetailthantheLaetoliprints.

（B）TheyareofmorerecentoriginthantheLaetoliprints.

（C）TheyarenotasinformativeastheLaetoliprints.

（D）TheyaremoredifficulttostudythantheLaetoliprints

30.Whichofthefollowingtermsisdefinedinthepassage?

（A）"hominids"（line3）

（B）"arch"（line9）

（C）"photogrammetry"（line16）

（D）"siliconresinmolds"（line29）

Questions31-40

Thelivelihoodofeachspeciesinthevastandintricateassemblageoflivingthingsdependsontheexistencesofotherorganisms.Thisinterdependenceissometimessubtle,sometimesobvious.Perhapsthemoststraightforwarddependenceofonespeciesonanotheroccurswithparasites,organismsthatliveonorinotherlivingthingsandderivenutrientsdirectlyfromthem.Theparasiticwayoflifeiswidespread.Amultitudeofmicroorganisms（includingvirusesandbacteria）andanarmyofinvertebrates–orcreatureslackingaspinalcolumn（includingcrustaceans,insects,andmanydifferenttypesofworms）–maketheirlivingsdirectlyattheexpenseofothercreatures.Inthefaceofthisonslaught,livingthingshaveevolvedavarietyofdefensemechanismsforprotectingtheirbodiesfrominvasionbyotherorganisms.

Certainfungiandevensomekindsofbacteriasecretesubstancesknownasantibioticsintotheirexternalenvironment.Thesesubstancesarecapableofkillingorinhibitingthegrowthofvariouskindsofbacteriathatalsooccupythearea,therebyeliminatingorreducingthecompetitionfornutrients.Thesameprincipleisusedindefenseagainstinvadersinothergroupsoforganisms.Forexample,whenattackedbydisease-causingfungiorbacteria,manykindsofplantsproducechemicalsthathelptowardofftheinvaders.

Membersoftheanimalkingdomhavedevelopedavarietyofdefensemechanismsfordealingwithparasites.Althoughthesemechanismsvaryconsiderably,allmajor

groupsofanimalsarecapableofdetectingandreactingtothepresenceof"foreign"cells.Infact,throughouttheanimalkingdom,fromspongestocertaintypesofworms,shellfish,andallvertebrates（creaturespossessingaspinalcolumn）,thereisevidencethattransplantsofcellsorfragmentsoftissuesintoananimalareacceptedonlyiftheycomefromgeneticallycompatibleorcloselyrelatedindividuals.

Theabilitytodistinguishbetween"self"and"nonself",whilepresentinallanimals,ismostefficientamongvertebrates,whichhavedevelopedanimmunesystemastheirdefensemechanism.Theimmunesystemrecognizesandtakesactionagainstforeigninvadersandtransplantedtissuesthataretreatedasforeigncells.

31.Whatdoesthepassagemainlydiscuss?

（A）howparasitesreproduce

（B）howorganismsreacttoinvaders

（C）howantibioticsworktocuredisease

（D）howtheimmunesystemsofvertebratesdeveloped

32.Theword"intricate"iiiline1isclosestinmeaningto

（A）difficult

（B）widespread

（C）critical

（D）complex

33.Theexpression"anarmy"inline6isclosestinmeaningto

（A）anillness

（B）anattack

（C）alargenumber

（D）adistincttype

34.Theexpression"anarmyinline6isclosestinmeaningto

（A）anillness

（B）anattack

（C）alargenumber

（D）adistincttype

35.Accordingtothepassage,someorganismsproduceantibioticsinorderto

（A）preventdiseaseinhumans

（B）aiddigestion

（C）fightoffotherorganisms

（D）createnewtypesofnutrients

35.Theword"vary"inline19isclosestinmeaningto

（A）differ

（B）endure

（C）balance

（D）contribute

36.Theword"they"inline23refersto

（A）sponges,wormsandshellfish

（B）vertebrates

（C）individuals

（D）transplants

37.Accordingtothepassage,atransplantoftissuebetweengeneticallyincompatibleorganismswillresultinthetransplantedtissue

（A）becomingaparasite

（B）beingtreatedasaninvader

（C）alteringitsgeneticmakeup

（D）developinganewimmunesystem

38.Accordingtothepassage,theabilitytodistinguishbetween"self"and"nonself"enablesvertebratesto

（A）accepttransplantedce