2026年托福《阅读》考场版真题

2026年托福《阅读》考场版真题Passage1TheMilankovitchtheoryproposesthatcyclicalchangesinEarth'sorbitalparametersaretheprimarydriversoflong-termclimatechange,particularlythetimingofglacialandinterglacialperiods.Whiletheideathatastronomicalcyclesinfluenceclimatewassuggestedasearlyasthemid-19thcentury,itwastheSerbianmathematicianandastronomerMilutinMilankovitchwho,intheearly20thcentury,mathematicallyformalizedtheserelationships.Hecalculatedhowvariationsinthreespecificorbitalparameters—eccentricity,obliquity,andprecession—affectthedistributionandintensityofsolarradiation(insolation)receivedbyEarth'ssurface.Thefirstparameter,orbitaleccentricity,referstotheshapeofEarth'sorbitaroundtheSun.Theorbitdeviatesfromaperfectcircle,rangingfromnearlycirculartoslightlyellipticaloveracycleofapproximately100,000years.Whentheorbitismoreelliptical,thedifferenceindistancebetweenEarthandtheSunatperihelion(closestapproach)andaphelion(farthestpoint)isgreater.However,contrarytosimpleintuition,itisnotthetotalamountofsolarradiationreceivedoverthecourseofayearthatdrivesiceages;thistotalvariesbyonlyabout0.2percent.Instead,thecriticalfactoristheseasonaldistributionofthisenergy.Ahigheccentricitycanamplifytheeffectsofothercycles,makingseasonsmoreextremeinonehemisphereandmoremoderateintheother,dependingonwherethesolsticesoccurrelativetotheperihelion.Thesecondparameter,axialobliquity,isthetiltofEarth'srotationaxisrelativetoitsorbitalplane.Thistiltvariesbetween22.1°and24.5°overaperiodofabout41,000years.Thecurrenttiltisapproximately23.5°.Thedegreeoftiltisfundamentaltotheexistenceofseasons;atiltofzerodegreeswouldmeannoseasonsatall,aseverypointonEarthwouldreceivethesameamountofsunlightyear-round.Agreatertiltresultsinmoreextremeseasons—hottersummersandcolderwinters—whilealessertiltleadstomilderseasons.Inthecontextofglaciation,theobliquitycycleisparticularlyimportantforhigh-latituderegions.Ahighertiltincreasessummerinsolationatthepoles.Ifsummersaretoocool,wintersnowandicemaynotfullymelt,allowingicesheetstoaccumulateovertime.Conversely,warmersummersdrivenbyhighertiltcanmelttheaccumulatedice,preventingthegrowthofglaciers.Thethirdparameter,axialprecession,describestheslowwobbleofEarth'saxis,similartothewobbleofaspinningtop.Thiswobblecausesthepositionofthesolsticesandequinoxestoshiftslowlyrelativetotheorbitoveracycleofroughly23,000years.PrecessiondetermineswhethertheNorthernHemispherepointstowardtheSunatperihelion(resultinginhottersummersandcolderwinters)orataphelion(resultingincoolersummersandmilderwinters).Becausethedistributionoflandmassesisasymmetric—EarthhassignificantlymorelandintheNorthernHemisphere—theprecessioncyclehasaprofoundeffectonglobalclimate.ThegrowthofcontinentalicesheetsoccursprimarilyintheNorthernHemisphereduetoitslandmassavailability.Therefore,whenprecessionalignstominimizeNorthernHemispheresummerinsolation(coolsummers),itcreatesfavorableconditionsforglaciation.Fordecades,theMilankovitchtheoryfacedskepticism,primarilybecausethegeologicaltimelineoficeagesdidnotseemtomatchthe100,000-yeareccentricitycycle,whichistheweakestofthethreeorbitalforcesintermsofinsolationchanges.Beforethemid-Pleistocenetransition,about1millionyearsago,glacialcyclesappearedtofollowthe41,000-yearobliquitycycle.However,around1millionyearsago,thedominantcycleshiftedto100,000years,aphenomenonknownasthe"Mid-PleistoceneTransition"orthe"100-kyrproblem."Varioushypotheseshavebeenproposedtoexplainthisshift,includinglong-termatmosphericcarbondioxidechangesandtheinteractionbetweenicesheetdynamicsandbedrockisostasy.Despitethesecomplexities,thevalidationoftheMilankovitchtheorycameinthe1970swiththeanalysisofdeep-seasedimentcores.ScientistsJamesHays,JohnImbrie,andNicholasShackletonanalyzedisotopicratiosofoxygen(O)inthefossilizedshellsofforaminifera.Theseratiosserveasaproxyforglobalicevolumeandtemperature.Theirspectralanalysisofthedatarevealeddistinctpeakscorrespondingexactlytothe23,000-year,41,000-year,and100,000-yearcyclespredictedbyMilankovitch.Thisstudyprovidedthefirstconclusiveempiricalevidencethatastronomicalcyclespacethetimingoftheiceages.Whiletheexactmechanismsbywhichtherelativelyweak100,000-yeareccentricitysignaldominatestherecentclimaterecordremaindebated,thecorrelationbetweenorbitalgeometryandclimatehistoryisnowacornerstoneofpaleoclimatology.1.Theword"formalized"inthepassageisclosestinmeaningtoA.standardizedB.definedC.publicizedD.complicated2.Accordingtoparagraph2,whyisorbitaleccentricitynotconsideredaprimarydriveroficeagesbasedsolelyontotalsolarradiation?A.BecausethetotalradiationreceivedbyEarthvariestoosignificantly.B.Becausethechangeintotalradiationistoosmalltoaccountforclimateshifts.C.BecauseeccentricityaffectstheSouthernHemispheremorethantheNorthern.D.Becausethecycleofeccentricityistoolongtoinfluenceseasonaltemperaturesaccurately.3.WhichofthefollowingcanbeinferredabouttheseasonsonEarthfromparagraph3?A.SeasonsarecausedentirelybytheeccentricityofEarth'sorbit.B.Adecreaseinaxialtiltwouldresultinlessseasonalvariation.C.Thecurrentaxialtiltisatitsmaximumpossiblevalue.D.Glaciersaremorelikelytoformduringperiodsofextremeseasonalvariation.4.Theword"profound"inthepassageisclosestinmeaningtoA.minimalB.theoreticalC.significantD.questionable5.Accordingtoparagraph4,whyistheprecessioncycleparticularlycriticalforthegrowthofNorthernHemisphereicesheets?A.TheNorthernHemispherehasmorelandmasssuitableforiceaccumulation.B.TheNorthernHemisphereisclosertotheSunduringprecessionevents.C.TheSouthernHemisphereoceanspreventicefromformingregardlessofprecession.D.ThewobbleeffectisstrongerintheNorthernHemisphereduetogravity.6.Whydoestheauthormentionthe"Mid-PleistoceneTransition"inparagraph5?A.ToprovideevidencethatsupportstheMilankovitchtheorywithoutreservation.B.Toillustrateahistoricalinconsistencyinthegeologicalrecordregardingthetheory.C.ToexplainhowcarbondioxidelevelsaffectthetiltofEarth'saxis.D.Toarguethatthe100,000-yearcycleisthemostpowerfulorbitalforce.7.Whichofthesentencesbelowbestexpressestheessentialinformationinthehighlightedsentenceinthepassage?(Highlightedsentence:"Varioushypotheseshavebeenproposedtoexplainthisshift,includinglong-termatmosphericcarbondioxidechangesandtheinteractionbetweenicesheetdynamicsandbedrockisostasy.")A.Scientistshaveusedcarbondioxidelevelsandbedrockisostasytoprovethatthe100,000-yearcycleisvalid.B.Theshiftinglacialcyclesremainsunexplainedbecausecarbondioxidedataisunavailable.C.Explanationsfortheshiftto100,000-yearcyclesinvolvefactorslikecarbondioxideandicesheetinteractions.D.Bedrockisostasyistheonlyhypothesisthatcanaccountforthechangeincyclelength.8.Theword"proxy"inthepassageisclosestinmeaningtoA.substituteB.catalystC.obstacleD.constant9.Lookatthefourletters[A,B,C,D]thatindicatewherethefollowingsentencecouldbeaddedtothepassage."However,theamountoficeontheplanetchangestheisotopiccompositionoftheoceanwater."[A]Despitethesecomplexities,thevalidationoftheMilankovitchtheorycameinthe1970swiththeanalysisofdeep-seasedimentcores.[B]ScientistsJamesHays,JohnImbrie,andNicholasShackletonanalyzedisotopicratiosofoxygen(O)inthefossilizedshellsofforaminifera.[C]Theseratiosserveasaproxyforglobalicevolumeandtemperature.[D]Theirspectralanalysisofthedatarevealeddistinctpeakscorrespondingexactlytothe23,000-year,41,000-year,and100,000-yearcyclespredictedbyMilankovitch.Wherewouldthesentencebestfit?A.[A]B.[B]C.[C]D.[D]10.Directions:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.Somesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareminorideasinthepassage.TheMilankovitchtheorylinkscyclicalchangesinEarth'sorbittothetimingofglacialandinterglacialperiods.____________________________________________________________A.MilutinMilankovitchusedmathematicalcalculationstodefinehoworbitalchangesaffectsolarradiation.B.Thethreemainorbitalparametersareeccentricity,obliquity,andprecession,eachaffectinginsolationdifferently.C.Deep-seasedimentcoresprovidedempiricalevidencethatmatchedthepredictedorbitalcycles.D.GlacierscanonlyformintheSouthernHemisphereduetothelackoflandmassinthenorth.E.The100,000-yearcycleisthestrongestorbitalforceintermsofinsolationchanges.F.EccentricityistheonlyparameterthataffectsthedistancebetweenEarthandtheSun.Passage2Theemergenceofpotteryinhumanprehistorymarksasignificanttechnologicalandculturaltransition,oftenassociatedwiththeNeolithicperiod.However,recentarchaeologicaldiscoveriesacrossEastAsia,particularlyinChinaandJapan,havepushedbackthedatesoftheearliestknownceramicvessels,revealingthatpotterywasbeingproducedbyhunter-gatherersocietieslongbeforetheadventofagriculture.Thisfindingchallengesthetraditionalviewthatpotterywasstrictlyabyproductofthesedentarylifestylerequiredforfarming,suggestinginsteadthatitservedcrucialfunctionsformobilepopulationsaswell.Theearliestpotteryvessels,knownas"IncipientJomon"inJapananddatingbackasfaras16,000yearsago,werelow-fired,relativelysoft,andoftenelaboratelydecoratedwithcordmarks(impressionsmadebytwistingcordsintothewetclay).Thesevesselsweretypicallydeep,bowl-shapedforms.Giventhefragilityandweightofthesevessels,theirutilityforhighlynomadicgroupsmightseemcounterintuitive.However,researchersbelievethattheprimarydriverfortheinventionofpotteryinthesecontextswasfoodprocessing.Specifically,potterywasidealforboilingandsteaming.ThedietoftheLatePaleolithichunter-gatherersintheseregionswasheavilyreliantontherichmarineresourcesavailablealongthecoastlines,aswellasnutsandacornsfoundinthevastdeciduousforests.Manyofthesefoodsourcesrequireextensiveprocessingtobeedibleandsafe.Forexample,acornscontainhighlevelsoftannins,whicharebitterandtoxicifconsumedinlargequantities.Whiletanninscanbeleachedoutbysoakingincoldwater,boilingisfarmoreefficient.Similarly,hard,driedbeansandcertaintubersaredifficulttoeatraw.Potteryallowedthesegroupstoexpandtheirdietarybreadthbyunlockingthenutritionalvalueofresourcesthatwereotherwiseindigestibleorlabor-intensivetoprepareusingtraditionalmethodslikeroastingoveranopenfire.Furthermore,theabilitytoboilfoodhadprofoundimplicationsfornutrientextractionandhealth.Boilingsoftenstoughfibers,makingfoodeasiertochewanddigest,whichisparticularlyimportantforinfantsandtheelderly.Italsosterilizesfood,killingparasitesandbacteriathatmightbepresentinmeatorfish,therebyreducingtheincidenceoffoodborneillness.Thecreationofnutrient-richbrothsthroughboilingalsoallowedfortheextractionoffatsandmineralsintotheliquid,providingavaluablesourceofcaloriesthatcouldbeeasilyconsumed.Thisdietaryflexibilitylikelycontributedtopopulationgrowthandsocialcomplexityevenbeforethedomesticationofplantsandanimals.Thetechnologicalshifttopotteryalsoreflectschangesinsocialorganizationandthecognitivecapabilitiesofearlyhumans.Theproductionofceramicsrequiresacomplexchainofoperations:selectingandpreparingrawclay,temperingitwithmaterialslikecrushedshellorsandtopreventcracking,shapingthevessel(oftenbycoiling),andfinallyfiringitatcontrolledtemperatures.Thisprocessimpliesatransmissionoftechnicalknowledgeacrossgenerationsandadegreeofplanningthatgoesbeyondtheimmediateneedsofthemoment.TheelaboratedecorationsfoundonearlyJomonpottery,suchasthe"flame-style"vessels,suggestthattheseobjectsheldsymbolicvaluebeyondtheirutilitarianfunction,perhapsservingasmarkersofgroupidentityorsocialstatuswithinthecommunity.AstheclimatewarmedattheendofthelastIceAge(thePleistocene),forestsexpandedandsealevelsrose,alteringtheavailableresources.Thisenvironmentalshift,knownastheHolocenetransition,createdconditionsfavorableforthedevelopmentofagriculture.Inthiscontext,thepre-existingknowledgeofpotterytechnologywasco-optedandadaptedforagriculturalneeds.Vesselsbecamelargerandmorestandardized,designedforstorageandprocessingofgrainsratherthanjustboilingmeatornuts.Thus,ratherthanbeingasuddeninventionsparkedbyagriculture,potterywasapre-existingtechnologythatwasgraduallyintegratedintotheNeolithicwayoflife,facilitatingthestorageandpreparationofsurpluscropsthatcharacterizedearlyfarmingsocieties.11.Theword"sedentary"inthepassageisclosestinmeaningtoA.settledB.activeC.agriculturalD.primitive12.Accordingtoparagraph2,whatcharacteristicistypicalofthe"IncipientJomon"pottery?A.Itwashigh-firedandextremelydurable.B.Itwasoftendecoratedwithimpressionsmadebycords.C.Itwasprimarilyusedforstoringdrygrains.D.Itwasinventedstrictlybyfarmingcommunities.13.Whydoestheauthormention"tannins"inparagraph3?A.Toexplainwhyacornswerenoteatenbyhunter-gatherers.B.Toillustrateachemicalcompoundthatimprovesthetasteoffood.C.Toprovideaspecificexampleofasubstancethatrequiresprocessingtoremovetoxins.D.Toarguethatboilingwaterwastheonlymethodofdetoxificationavailable.14.WhichofthefollowingisNOTmentionedinparagraph4asabenefitofboilingfood?A.Itmakesfoodeasiertochew.B.Itkillsharmfulbacteria.C.ItincreasesthevitaminCcontentsignificantly.D.Itallowsforthecreationofcalorie-richbroths.15.Theword"utilitarian"inthepassageisclosestinmeaningtoA.decorativeB.practicalC.symbolicD.fragile16.Accordingtoparagraph5,whatdoesthecomplexproductionprocessofearlypotterysuggestaboutthepeoplewhomadeit?A.Theyhadasettledlifestylewithpermanenthousing.B.Theypossessedtheabilitytotransmittechnicalknowledgeandplanahead.C.Theytradedextensivelywithneighboringagriculturalcommunities.D.Theyusedpotteryprimarilyforreligiousritualsratherthancooking.17.Theword"co-opted"inthepassageisclosestinmeaningtoA.discardedB.inventedC.adaptedD.replaced18.Accordingtoparagraph6,howdidthetransitiontoagricultureaffectpottery?A.Itledtoadeclineinpotteryproductionbecausemetalvesselsbecamepreferred.B.Itcausedpotterytobecomemoreelaborateanddecorative.C.Itresultedinchangesinpotterydesigntosuitthestorageandprocessingofgrains.D.Ithadnosignificanteffectbecausepotterywasalreadyfullydeveloped.19.Lookatthefourletters[A,B,C,D]thatindicatewherethefollowingsentencecouldbeaddedtothepassage."Thiscapabilitywouldhavebeenespeciallyadvantageousduringthecoldermonthsoftheyear."[A]Theabilitytoboilfoodhadprofoundimplicationsfornutrientextractionandhealth.[B]Boilingsoftenstoughfibers,makingfoodeasiertochewanddigest,whichisparticularlyimportantforinfantsandtheelderly.[C]Italsosterilizesfood,killingparasitesandbacteriathatmightbepresentinmeatorfish,therebyreducingtheincidenceoffoodborneillness.[D]Thecreationofnutrient-richbrothsthroughboilingalsoallowedfortheextractionoffatsandmineralsintotheliquid,providingavaluablesourceofcaloriesthatcouldbeeasilyconsumed.Wherewouldthesentencebestfit?A.[A]B.[B]C.[C]D.[D]20.Directions:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.Somesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareminorideasinthepassage.Recentarchaeologicalevidenceindicatesthatpotterywasinventedbyhunter-gatherers,notjustfarmers,andplayedakeyroleinearlyhumansocieties.____________________________________________________________A.TheinventionofpotteryisdirectlylinkedtothedomesticationofdogsintheJomonperiod.B.Potteryallowedpre-agriculturalsocietiestoprocesstoxicfoodslikeacornsandimprovenutrientextractionthroughboiling.C.Theproductionofpotteryrequiredadvancedcognitiveskillsandsociallearning,asseeninthedecoratedJomonvessels.D.Agricultureledtothedeclineofpotterybecausepeoplepreferredtoeatfreshfoods.E.Earlypotterywasoftenfragileandimpracticalfornomadicgroupswhoneededtotravellight.F.Asagriculturedeveloped,existingpotterytechnologywasmodifiedtomeetnewneedslikegrainstorage.Passage3Theconceptofanimalplayhaslongfascinatedbiologistsandpsychologists,asitappearstobeawidespreadbehavioracrosstheanimalkingdom,observedinmammals,birds,andevensomereptilesandinsects.Playbehaviortypicallyinvolvesactionsthatareexaggerated,repetitive,andlackimmediate,obviousutility.Forexample,apredatorkittenmightstalkandpounceonaleaf,orayoungmonkeymightrepeatedlygraspandreleaseabranch.Becauseplayconsumesenergyandcarriespotentialrisks(suchasinjuryorattractingtheattentionofpredators),itsevolutionarypersistencesuggeststhatitservessignificant,albeitdelayed,benefitsforthedevelopinganimal.Severalhypotheseshavebeenproposedtoexplaintheadaptivefunctionofplay.Oneofthemostprominentisthe"motortraininghypothesis."Thistheorysuggeststhatplayfunctionsasphysicalexerciseandpracticeformotorskillsthatwillbeessentialinadulthood.Byengaginginvigorousphysicalactivities,younganimalsstrengthentheirmuscles,improvetheircoordination,andrefinetheircardiovascularsystems.Inspecieswheresurvivaldependsoncomplexmotorsequences—suchashunting,escapingpredators,ornavigatingcomplexarborealenvironments—playprovidesasafeenvironmenttopracticethesesequences.Forinstance,youngungulates(hoofedmammals)oftenengageinplayfulrunningandleaping,whichlikelyimprovestheirabilitytoescapefromswiftpredatorslaterinlife.Arelatedbutdistincttheoryisthe"trainingfortheunexpectedhypothesis."Proponentsofthisviewarguethatplayhelpsanimalscopewithnovelandunpredictablesituations.Duringplay,animalsoftencombineactionsinnovelwaysoroverreacttostimuli(e.g.,adogmightover-dramatizeaplaybow).Thisvariabilityhelpstobuildarepertoireofflexibleresponses,enhancingtheanimal'sabilitytoadapttosuddenchangesintheenvironment.Ifananimalonlypracticedrigid,stereotypedmovements,itmightfailwhenfacedwithauniquethreatoropportunity.Play,byitsverynature,introducesvariabilityandrandomness,effectively"training"theneuralcircuitstohandletheunexpected.Socialplayisanothermajorcategory,encompassinginteractionssuchaswrestling,chasing,andplay-fighting.The"socialtraininghypothesis"positsthattheseinteractionsarecrucialforthedevelopmentofsocialskillsandtheestablishmentofdominancehierarchies.Throughplay-fighting,animalslearntherulesofengagement—howtosignalintent,howtoinhibittheforceoftheirbitestoavoidinjuringpeers,andhowtorecognizewhentogiveup.Theseinteractionshelpindividualsnavigatethecomplexsocialdynamicsoftheirgroups.Forexample,inrats,peerplayduringadolescenceislinkedtogreatersocialcompetenceandreducedaggressioninadulthood.Theabilitytodifferentiatebetweenplayandseriousaggressionisacriticalsocialskillthatpreventsunnecessaryviolencewithinthegroup.Despitethesecompellingtheories,determiningtheexactfunctionofplayismethodologicallychallenging.Onedifficultyisthatplayismultifaceted;asingleplayboutcaninvolvephysical,cognitive,andsocialelementssimultaneously.Additionally,thebenefitsofplayareoftendeferred,meaningtheymanifestonlymuchlaterintheanimal'slife,makingithardtoestablishadirectcausallinkbetweenaspecificplayepisodeandanincreaseinfitness.Someresearchershaveproposedthatplaymightbea"spandrel"—abyproductofotherevolutionaryadaptations—ratherthanadirectadaptationitself.However,thesheercostofplayintermsofenergyandriskmakesthe"spandrel"explanationlesslikely;naturalselectionwouldpresumablyweedoutsuchcostlybehaviorifitdidnotconferanetadvantage.Recentneurobiologicalstudieshaveshedlightonthemechanismsunderlyingplay,revealingthatitisnotmerelyalackofseriousactivitybutadistinctmotivationalstate.Playbehaviorisassociatedwiththeactivationofspecificneuralpathways,particularlythoseinvolvingdopamineandopioidsystemsinthebrain.Thesesystemsarerelatedtorewardandpleasure,suggestingthatplayisintrinsicallyenjoyableforanimals.Thisintrinsicrewardmechanismensuresthatyounganimalsengageinplayfrequently,evenwithoutexternalincentives.Thepresenceofthesededicatedneuralcircuitssupportstheideathatplayisabiologicallyfundamental,evolvedbehavior,deeplyembeddedinthephysiologyofmanyspecies.21.Theword"utility"inthepassageisclosestinmeaningtoA.amusementB.usefulnessC.electricityD.origin22.Accordingtoparagraph2,whatisthemainideaofthemotortraininghypothesis?A.Playhelpsanimalslearnhowtohuntspecificprey.B.Playisaformofexercisethatimprovesphysicalstrengthandcoordination.C.Animalsplaytoshowdominanceovertheirpeers.D.Playisawasteofenergythathasnorealpurpose.23.Whydoestheauthormentionadogover-dramatizingaplaybowinparagraph3?A.Toillustratehowplaycanhelpanimalstrainforunpredictablesituations.B.Toshowthatdogsaremoreintelligentthanotheranimals.C.Toprovethatplayfightingcanleadtorealaggression.D.Todemonstratethatplayispurelyforentertainment.24.Theword"inhibit"inthepassageisclosestinmeaningtoA.increaseB.encourageC.restrainD.initiate25.Accordingtoparagraph4,whatisabenefitofsocialplay-fightingforanimalslikerats?A.Itallowsthemtoestablishpermanentleadershiproles.B.Ithelpsthemlearntocontroltheiraggressionandinterpretsocialsignals.C.Itincreasestheirmusclemassmorethansolitaryplay.D.Itpreparesthemforhuntinginpacks.26.Whichofthefollowingismentionedinparagraph5asachallengeforresearchersstudyingplay?A.Playistooraretoobserveinthewild.B.Thebenefitsofplayareoftenimmediate,makingthemhardtomeasure.C.Playinvolvesmultipleelementsanditsbenefitsmayappearlaterinlife.D.Mostanimalsdonotplayincaptivity.27.Whatdoestheauthorimplyaboutthe"spandrel"hypothesisinparagraph5?A.Itisthemostwidelyacceptedexplanationforanimalplay.B.Itisunlikelybecauseplayistoocostlytobeamerebyproduct.C.Itexplainswhyplayisassociatedwithdopaminerelease.D.Ithasbeenprovenfalsebyrecentneurobiologicalstudies.28.Accordingtoparagraph6,whatroledodopamineandopioidsystemsplayinplaybehavior?A.Theycausetheanimaltofeeltiredafterplaying.B.Theyareresponsibleforthephysicalmovementsinvolvedinplay.C.Theymakeplaybehaviorenjoyableandrewarding.D.Theyhelptheanimaldistinguishbetweenplayandreality.29.Lookatthefourletters[A,B,C,D]thatindicatewherethefollowingsentencecouldbeaddedtothepassage."Thisdistinctionisvitalbecauserealcombatcouldleadtoseriousinjuryordeath."[A]Throughplay-fighting,animalslearntherulesofengagement—howtosignalintent,howtoinhibittheforceoftheirbitestoavoidinjuringpeers,andhowtorecognizewhentogiveup.[B]Theseinteractionshelpindividualsnavigatethecomplexsocialdynamicsoftheirgroups.[C]Forexample,inrats,peerplayduringadolescenceislinkedtogreatersocialcompetenceandreducedaggressioninadulthood.[D]Theabilitytodifferentiatebetweenplayandseriousaggressionisacriticalsocialskillthatpreventsunnecessaryviolencewithinthegroup.Wherewouldthesentencebestfit?A.[A]B.[B]C.[C]D.[D]30.Directions:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.Somesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareminorideasinthepassage.Animalplayisacostlybutwidespreadbehaviorthatlikelyservesseveralimportantdevelopmentalfunctions.____________________________________________________________A.Themotortraininghypothesissuggestsplayrefinesphysicalskillsneededforsurvival.B.Playisonlyobservedinmammalsandbirdsandisabsentinreptiles.C.Socialplayhelpsanimalsdeveloptheskillsnecessaryforgroupcohesionandcommunication.D.Neurobiologicalevidenceindicatesthatplayisdrivenbyspecificbrainrewardsystems.E.Animalsplayprimarilytoattractmatesandreproduce.F.Researchershaveconclusivelyproventhatplayhasnoevolutionarypurpose.***答案与解析Passage11.B解析：词汇题。“Formalized”在文中指Milankovitch将前人的想法用数学形式“定义”或“系统化”了。Standardized（标准化）有干扰，但defined更贴切“确立形式”的含义。Publicized（宣传）和complicated（使复杂）不符合语境。2.B解析：事实信息题。根据第二段，“itisnotthetotalamountofsolarradiationreceivedoverthecourseofayearthatdrivesiceages;thistotalvariesbyonlyabout0.2percent.”（驱动冰期的不是全年接收的太阳辐射总量；这个总量仅变化约0.2%）。因此，仅基于总辐射量的变化太小，不足以解释气候变化。3.B解析：推断题。第三段提