2025年7月托福考试回忆

2025年7月托福考试回忆

【ReadingSection】

Passage1

TheDevelopmentofthePeriodicTable

Theperiodictableoftheelementsisoneofthemostsignificantachievementsinthehistoryofchemistry.Itorganizesallknownchemicalelementsbasedontheiratomicnumber,electronconfigurations,andrecurringchemicalproperties.Thejourneytoitscurrentformwasneitherlinearnorsolitary,involvingthecontributionsofseveralscientistsovercenturies.

Intheearly19thcentury,JohannDöbereinerobservedthatcertaingroupsofthreeelements,whichhecalled"triads,"hadsimilarchemicalproperties.Forexample,lithium,sodium,andpotassiumformedatriadwheretheatomicweightofthemiddleelementwasapproximatelytheaverageoftheothertwo.Thiswasoneofthefirstattemptstofindapatternamongtheelements,thoughitwaslimitedinscope.

AmoresystematicapproachwastakenbyJohnNewlands,whoproposedthe"LawofOctaves"in1864.Henoticedthatwhenelementswerearrangedinorderofincreasingatomicweight,everyeighthelementseemedtosharepropertieswiththefirst,muchlikenotesinamusicalscale.Whilethisideahadmerit,itwasridiculedbysomecontemporariesbecauseitfailedtoaccountforthetransitionmetalsandseemedforcedinplaces.

Thebreakthroughcamein1869whenDmitriMendeleevpublishedhisperiodictable.Mendeleev'sgeniuslaynotonlyinarrangingtheelementsbutalsoinleavinggapsinhistablewherehepredictedundiscoveredelementsshouldexist.Heevendescribedthepropertiesofthesemissingelements,suchas"eka-silicon,"whichwaslaterdiscoveredasgermanium.Hispredictionswereremarkablyaccurate,whichconvincedthescientificcommunityofthetable'svalidity.

However,Mendeleevarrangedelementsbyatomicweight,notatomicnumber.Thiscausedafewinconsistencies.Forinstance,iodineandtelluriumappearedtobeoutoforderbasedonweightbutfitbetterchemicallyifiodinewasplacedaftertellurium.Thereasonforthisanomalywasnotunderstooduntiltheearly20thcenturywhenHenryMoseleydiscoveredthatthefundamentalpropertydetermininganelement'spositionwasitsatomicnumber(thenumberofprotons),notitsatomicweight.Moseley'sworkresolvedthediscrepanciesandledtothemodernperiodiclaw.

Questions:

1.Accordingtoparagraph2,whatwasalimitationofDöbereiner's"triads"?

A.Theywerebasedonelectronconfigurationsratherthanatomicweight.

B.Theyonlyappliedtoasmallnumberofknownelements.

C.Theyfailedtopredicttheexistenceofnewelements.

D.Theyarrangedelementsinorderofincreasingatomicnumber.

2.Theword"systematic"inthepassageisclosestinmeaningto:

A.methodical

B.theoretical

C.complex

D.rapid

3.Whydoestheauthormention"notesinamusicalscale"inparagraph3?

A.ToexplainwhyNewlands'theorywasrejectedbymusicians.

B.ToillustratethepatternNewlandsobservedinelementproperties.

C.Tosuggestthatchemistryisfundamentallysimilartomusic.

D.Tohighlighttheartisticnatureofearlyscientificdiscovery.

4.WhichofthefollowingcanbeinferredaboutMendeleev'speriodictablefromparagraph4?

A.Itwasimmediatelyacceptedwithoutanyskepticism.

B.Itincludedalltheelementsknownatthetimewithoutgaps.

C.Itallowedforthepredictionofelementsthathadnotyetbeendiscovered.

D.Itarrangedelementsstrictlyaccordingtotheiratomicnumber.

5.Accordingtoparagraph5,whydidMendeleevplaceiodineaftertelluriumdespitetheiratomicweights?

A.Hemadeamistakeinhiscalculations.

B.Theirchemicalpropertiessuggestedthisarrangementwasmorelogical.

C.HewantedtoalignhistablewithNewlands'LawofOctaves.

D.Iodinewasdiscoveredlaterthantellurium.

6.Theword"anomaly"inthepassageisclosestinmeaningto:

A.pattern

B.innovation

C.deviation

D.principle

7.HowdidMoseley'scontributionimproveuponMendeleev'stable?

A.Heintroducedtheconceptofelectronconfigurations.

B.Herearrangedthetablebasedonatomicnumberinsteadofatomicweight.

C.Hediscoveredtheelement"eka-silicon."

D.HeprovedthattheLawofOctaveswasmathematicallycorrect.

8.Lookatthefoursquares[■]thatindicatewherethefollowingsentencecouldbeaddedtothepassage.

Thisdiscoveryprovidedthefinalpieceofthepuzzleneededtosolidifythetable'sstructure.

Wherewouldthesentencebestfit?

A.Thereasonforthisanomalywasnotunderstooduntiltheearly20thcentury[■]whenHenryMoseleydiscoveredthatthefundamentalpropertydetermininganelement'spositionwasitsatomicnumber(thenumberofprotons),notitsatomicweight.

B.Mendeleev'sgeniuslaynotonlyinarrangingtheelementsbutalsoinleavinggapsinhistable[■]wherehepredictedundiscoveredelementsshouldexist.

C.Thiswasoneofthefirstattemptstofindapatternamongtheelements[■],thoughitwaslimitedinscope.

D.Itorganizesallknownchemicalelementsbasedontheiratomicnumber[■],electronconfigurations,andrecurringchemicalproperties.

9.Directions:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.Somesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareminorideasinthepassage.

Themodernperiodictableistheresultofthecumulativeworkofmanyscientists.

A.Döbereineridentifiedtriadsofelementswithsimilarproperties,butthissystemwastoolimited.

B.NewlandsproposedtheLawofOctaves,whichorganizedelementsintorepeatinggroupsofeight.

C.Mendeleevcreatedatablethatpredictedundiscoveredelementsbutreliedonatomicweight.

D.Chemistrybecamethemostpopularscienceinthe19thcenturyduetothesediscoveries.

E.Moseleyestablishedthatatomicnumber,notatomicweight,isthekeytoorderingelements.

F.Theperiodictableisnowusedprimarilyforteachingmusictheoryinschools.

Passage2

GlacialCyclesandMilankovitchCycles

Foroveracentury,geologistshavedebatedthecausesofthecyclicaladvancesandretreatsofglaciers,knownasglacial-interglacialcycles.ThemostwidelyacceptedtheorytodaylinksthesecyclestovariationsinEarth'sorbitalgeometry,collectivelyknownasMilankovitchcycles.ThesecyclesalterthedistributionandintensityofsunlightreceivedbyEarth,therebyinfluencingclimate.

TherearethreemaincomponentsofMilankovitchcycles:eccentricity,obliquity,andprecession.EccentricityreferstotheshapeofEarth'sorbitaroundtheSun,whichchangesfromnearlycirculartoslightlyellipticaloveracycleofabout100,000years.Whentheorbitismoreelliptical,thedifferenceinsolarradiationbetweenperihelion(closestapproachtotheSun)andaphelion(farthestpoint)isgreater.

Obliquity,orthetiltofEarth'saxis,variesbetween22.1°and24.5°overaperiodofapproximately41,000years.Thetiltisresponsiblefortheseasons;agreatertiltresultsinmoreextremeseasons(hottersummersandcolderwinters),whilealessertiltleadstomilderseasons.Thisvariationiscriticalbecauseitaffectstheintensityofsummersunlightinhighlatitudes,whichdetermineswhetherwintersnowaccumulatesormelts.

PrecessionisthewobbleofEarth'saxisonitsspin,similartoaspinningtop.Thiswobblechangesthetimingoftheseasonsrelativetotheorbitalposition,completingacycleevery23,000years.Currently,theNorthernHemisphereexperiencessummerwhenEarthisfarthestfromtheSun,whichmoderatesthesummerheat.Inthepast,precessioncausedtheNorthernHemispheretohavesummerwhenEarthwasclosesttotheSun,amplifyingtheheat.

TheMilankovitchtheorysuggeststhatglacialperiodsbeginwhensummerinsolation(incomingsolarradiation)athighnorthernlatitudesisinsufficienttomeltthepreviouswinter'ssnowpack.Theaccumulationofsnowoverthousandsofyearsleadstotheformationoficesheets.Conversely,interglacialperiodsoccurwhensummerinsolationincreases,meltingtheicesheets.Whiletheorbitalcyclesprovidethe"pacemaker"fortheiceages,feedbackmechanismswithintheclimatesystem,suchasthealbedoeffect(reflectivityofice)andgreenhousegasconcentrations,amplifytherelativelyweakorbitalforcing.

Questions:

1.Theword"collectively"inthepassageisclosestinmeaningto:

A.theoretically

B.together

C.controversially

D.scientifically

2.Accordingtoparagraph3,howdoesobliquityaffecttheclimate?

A.ItchangestheshapeofEarth'sorbit.

B.Itdeterminesthelengthoftheyear.

C.Itinfluencestheseverityoftheseasons.

D.ItcausesthewobbleofEarth'saxis.

3.Whydoestheauthormention"aspinningtop"inparagraph4?

A.TodescribetheshapeofEarth'sorbit.

B.Toprovideananalogyforthemovementofprecession.

C.Toexplainwhytheseasonschange.

D.Toillustratetheconceptofeccentricity.

4.Whatcanbeinferredfromparagraph4aboutthecurrentclimatestatusoftheNorthernHemisphere?

A.Itiscurrentlyinaglacialperiod.

B.ItssummersarehotterbecauseEarthisclosesttotheSun.

C.ItssummersaremilderbecauseEarthisfarthestfromtheSun.

D.Itswintersarecolderduetoincreasedaxialtilt.

5.Theword"insolation"inthepassageisclosestinmeaningto:

A.isolation

B.insulation

C.solarradiation

D.temperature

6.Accordingtoparagraph5,whatroledofeedbackmechanismsplayintheclimatesystem?

A.TheycounteracttheeffectsofMilankovitchcycles.

B.Theyaretheprimarycauseoficeages.

C.Theyintensifytheclimaticchangesinitiatedbyorbitalvariations.

D.Theyhavenosignificantimpactonglobaltemperatures.

7.WhichofthefollowingistrueregardingthetimingofMilankovitchcycles?

A.Eccentricity,obliquity,andprecessionalloccuronthesametimescale.

B.Eccentricityhastheshortestcycleduration.

C.Precessioncyclesoccurapproximatelyevery23,000years.

D.Obliquitychangesoccurover100,000years.

8.Thepassagesupportswhichofthefollowingstatementsabouttheformationoficesheets?

A.Icesheetsformwhenwintersnowfailstomeltcompletelyduringthesummer.

B.Icesheetsareprimarilycausedbyincreasedgreenhousegases.

C.IcesheetsformonlywhenEarth'sorbitisperfectlycircular.

D.Icesheetsgrowfastestduringperiodsofhighsummerinsolation.

9pletethesummary.

MilankovitchcyclesexplainthetimingofglacialandinterglacialperiodsthroughchangesinEarth'sorbit.

A.EccentricityinvolveschangesintheshapeofEarth'sorbitover100,000years.

B.ObliquityreferstothetiltofEarth'saxisandaffectsseasonalintensity.

C.Precessionisthewobbleoftheaxisthatchangesthetimingofseasons.

D.Thetheoryiscompletelyrejectedbymoderngeologists.

E.Feedbackmechanismslikealbedoamplifytheorbitaleffects.

F.GlaciersadvanceonlywhentheEarthisclosesttotheSun.

Passage3

TheArchitectureofMesoamericanCities

Mesoamericancities,particularlythoseoftheMayaandtheAztecs,exhibiteduniquearchitecturalandurbanplanningcharacteristicsthatdistinguishedthemfromtheirEuropeancounterparts.Unliketheorganic,oftensprawlinggrowthofmedievalEuropeancities,Mesoamericanurbancentersweretypicallylaidoutaccordingtocosmologicalprinciplesandrigidgrids.

Thecitycenter,ortheceremonialprecinct,wastheheartoftheMesoamericancity.Thisareawasdominatedbymassivepyramids,temples,andballcourts,allarrangedaroundacentralplaza.Thepyramidsoftenrepresentedmountains,whichwereconsideredsacredsourcesofwaterandfertilityinMesoamericancosmology.Theorientationofthesestructureswasastronomicallyaligned,frequentlyfacingcardinaldirectionsorspecificcelestialeventsliketheequinoxes.

Residentialareasextendedoutwardfromtheceremonialcenter.InTeotihuacan,forexample,thecitywasdividedintodistinctapartmentcompounds.Thesecompoundshousedlargenumbersofpeople,suggestingadegreeofsocialorganizationandpossiblycommunalliving.The"AvenueoftheDead,"abroadcentralstreet,ranthroughthecityandservedasaprocessionalway,connectingthemajortemplecomplexes.Thisavenueemphasizedthehierarchicalnatureofthecity,guidingtheeyeandthefeettowardtheseatsofpower.

WatermanagementwasanothercriticalaspectofMesoamericanarchitecture.CitieslikeTikalwerebuiltinrainforestenvironmentswithseasonalrainfall.Tomanagewaterresources,theMayaconstructedreservoirs,dams,andcanalstocaptureandstorerainwaterforthedryseason.Thisinfrastructurewasvitalforsupportinglargepopulationsinareaswheresurfacewaterwasscarceduringpartsoftheyear.

TheAzteccapital,Tenochtitlan,builtonanislandinLakeTexcoco,tookwatermanagementtoanotherlevel.Thecitywasconnectedtothemainlandbycausewaysandfeaturedchinampas,orfloatinggardens,whichwerehighlyproductiveagriculturalplots.TheAztecsalsobuiltdikesystemstocontrolfloodingandseparatefreshandsaltwater.ThisengineeringprowessallowedTenochtitlantobecomeoneofthelargestcitiesintheworldatthetimeoftheSpanisharrival.

Questions:

1.Accordingtoparagraph1,howdidMesoamericancitiestypicallydifferfrommedievalEuropeancities?

A.Theyweresmallerinpopulation.

B.Theylackedacentralplanningstructure.

C.Theywereorganizedbasedoncosmologicalandgridprinciples.

D.Theywerebuiltprimarilyfordefensivepurposes.

2.Theword"cosmological"inthepassageisclosestinmeaningto:

A.relatingtotheuniverse

B.economic

C.political

D.military

3.Whatisthemainfunctionofthecentralplazadescribedinparagraph2?

A.Toserveasamarketplacefortrade.

B.Toactasafocalpointforceremonialandreligiousactivities.

C.Toprovidehousingfortheelite.

D.Tobeusedasadefensivefortification.

4.Whydoestheauthormentionthe"AvenueoftheDead"inparagraph3?

A.Toillustratethegridsystemusedinresidentialplanning.

B.Todemonstratetheimportanceofprocessionalroutesandhierarchy.

C.Toshowhowthecitywasdefendedagainstinvaders.

D.ToexplainthewatermanagementsystemofTeotihuacan.

5.Accordingtoparagraph4,whywaswatermanagementcrucialfortheMaya?

A.Theylivedinadesertenvironment.

B.Theyneededtopreventconstantflooding.

C.Theyexperiencedseasonaldroughtsintherainforest.

D.Theyreliedonfishingastheirmainfoodsource.

6.Theword"prowess"inthepassageisclosestinmeaningto:

A.failure

B.skill

C.neglect

D.theory

7.WhichofthefollowingismentionedasafeatureofTenochtitlan?

A.Floatinggardenscalledchinampas.

B.Alargewallsurroundingtheentirecity.

C.Pyramidsmadeentirelyofgold.

D.Alackofanyconnectiontothemainland.

8.WhatcanbeinferredaboutthesocialstructureofTeotihuacanfromthementionof"apartmentcompounds"?

A.Peoplelivedinisolatedsingle-familyhomes.

B.Socialorganizationwascomplexandpossiblycommunal.

C.Thecitywasprimarilyinhabitedbynomads.

D.Therewasnodistinctionbetweenrichandpoor.

9pletethesummary.

Mesoamericancitiesweresophisticatedurbancenterswithdistinctarchitecturalfeatures.

A.Citieswereoftenplannedaroundaceremonialcenterwithastronomicallyalignedstructures.

B.TheMayaandAztecsusedidenticalbuildingmaterials.

C.Residentialareaswereoftenorganizedintocompoundsorconnectedbycauseways.

D.Watermanagementwasessentialduetoenvironmentalchallenges.

E.EuropeancitiesweremodeledafterTeotihuacan.

F.Theballcourtswereusedexclusivelyforsoccergames.

【ListeningSection】

Conversation1

Professor:Hi,Sarah,youwantedtoseemeaboutyourtermpaper?

Student:Yes,ProfessorMiller.I'mplanningtowriteabouttheimpactofdeforestationonbiodiversityintheAmazon.ButI'mhavingtroublenarrowingdownmytopic.

Professor:That'sagoodstart,butitisindeedverybroad.Youcan'tcovertheentireAmazoninatenpaper.Maybefocusonaspecificspeciesoraspecificregion?

Student:IwasthinkingaboutfocusingontheToucan.Youknow,thebird.

Professor:Interestingchoice.Toucansarewhatwecall"keystonespecies."Theirfeedinghabitshelpdisperseseedsformanytrees.Iftoucansdisappear,theforestcompositionchangesdrastically.

Student:Exactly.Ireadthattheypreferlargefruitfrombigtrees,whicharetheonesmostlikelytobelogged.

Professor:Right.Soyoucouldinvestigatethecorrelationbetweenloggingdensityandtoucanpopulationdecline.OrperhapslookathowthereductionintoucansaffectstheregenerationofspecifictreespeciesliketheFigtree.

Student:TheFigtreeanglesoundsfascinating.SoIcouldarguethatloggingtoucans'habitatindirectlyleadstothedeclineofFigtrees,whichaffectsotheranimalsthatrelyonfigs.

Professor:Precisely.Thatcreatesacascadingeffect.Justmakesureyoufindrecentstudiesthatsupportthislink.Ithinktherewasastudypublishedlastyearinthe"JournalofTropicalEcology"thatmightberelevant.

Student:Thanks,Professor.I'lllookthatupimmediately.

Questions:

1.Whatisthestudent'sproblem?

A.ShecannotfindenoughsourcesontheAmazon.

B.Herchosentopicistoobroad.

C.Shedoesnotunderstandtheassignmentrequirements.

D.Shewantstochangehertopiccompletely.

2.Whatdoestheprofessorsuggestfocusingon?

A.Theeconomicimpactoflogging.

B.ThegeneraldietofAmazonianbirds.

C.TherelationshipbetweenToucansandspecifictreespecies.

D.Thehistoryofdeforestationlaws.

3.Whydoestheprofessormention"keystonespecies"?

A.ToexplainwhyToucansareimportanttotheecosystem.

B.Tosuggestthatthestudentstudyrocksinstead.

C.Todefinethetermforthestudent'sexam.

D.ToindicatethatToucansareendangered.

4.Whatisthestudent'sfinaldecisionforthepapertopic?

A.TheeconomicvalueofToucans.

B.TheimpactofToucandeclineonFigtrees.

C.TheloggingmethodsintheAmazon.

D.ThematinghabitsofToucans.

5.Whatdoestheprofessorrecommendthestudentdonext?

A.Interviewabiologist.

B.Changetheclass.

C.Findaspecificstudyinajournal.

D.VisittheAmazonrainforest.

Lecture1:Physics(ThePhotoelectricEffect)

Professor:Todaywearediscussingthephotoelectriceffect,aphenomenonthathelpedestablishquantummechanics.Simplyput,whenlightshinesonametalsurface,electronscanbeejectedfromthatmetal.Thisiscalledphotoemission.

Now,classicalphysicspredictedthattheintensity(brightness)ofthelightshoulddeterminetheenergyoftheejectedelectrons.Abrighterlightshouldknockelectronsoutwithmorespeed.However,experimentsshowedthatthiswasn'tthecase.Instead,thefrequency(color)ofthelightdeterminedtheenergy.Redlight,regardlessofhowbright,mightnotejectanyelectrons,whileafaintbluelightcouldejectenergeticelectrons.

Einsteinexplainedthisin1905byproposingthatlightconsistsofdiscretepacketsofenergycalled"photons."TheenergyofaphotonisgivenbytheequationE=hf,whereEisenergy,hisPlanck'sconstant,andfisfrequency.Ifaphotonhitsanelectronanditsenergyisgreaterthanthe"workfunction"(theenergybindingtheelectrontothemetal),theelectronescapes.Anyextraenergybecomestheelectron'skineticenergy.

Thisdiscoverywaspivotalbecauseitshowedthatlightbehavesasaparticle,notjustawave.Thiswave-particledualityisacornerstoneofmodernphysics.

Questions:

1.Whatisthemaintopicofthelecture?

A.Thehistoryofmetalmanufacturing.

B.Thephotoelectriceffectanditsimplications.

C.Thepropertiesofelectronsinavacuum.

D.Classicalmechanicsvs.Relativity.

2.Accordingtotheprofessor,whatdidclassicalphysicsincorrectlypredictaboutthephotoelectriceffect?

A.Thatlightfrequencyaffectselectronenergy.

B.Thatlightintensityaffectselectronenergy.

C.Thatelectronsareneverejected.

D.Thatmetalabsorbslight.

3.HowdoestheprofessorexplainEinstein'scontribution?

A.Einsteinprovedthatlightisonlyawave.

B.Einsteinintroducedtheconceptofphotons.

C.EinsteincalculatedPlanck'sconstant.

D.Einsteindisprovedtheexistenceofelectrons.

4.IntheequationE=hf,whatdoesfrepresent?

A.Thespeedoflight.

B.Planck'sconstant.

C.Thefrequencyofthelight.

D.Theenergyoftheelectron.

5.Whatdoestheterm"workfunction"referto?

A.Theenergyrequiredtoremoveanelectronfromthemetal.

B.Theenergyoftheincomingphoton.

C.Thekineticenergyoftheejectedelectron.

D.Theintensityofthelightsource.

Lecture2:ArtHistory(PopArt)

Professor:Movingontothemid-20thcentury,wehavePopArt.Thismovementemergedinthe1950sinBritainandtheUnitedStates.PopArtchallengedtraditionsoffineartbyincludingimageryfrompopularculture,suchasadvertising,comicbooks,andmundanemass-producedobjects.

OneofthemostfamousfiguresisAndyWarhol.Hisworks,liketheCampbell'sSoupCans,exploretherelationshipbetweenartisticexpression,celebrityculture,andadvertisement.Byusingsilk-screening,atechniqueusedforcommercialprinting,Warholremovedthe"artist'shand"fromthework,suggestingthatartcouldbemechanicalandreproducible.

Anotherkeyartist,RoyLichtenstein,createdpaintingsthatlookedexactlylikecomicbookpanels.HeusedheavyblackoutlinesandBen-Daydots—aprintingmethodforcreatingshadingandsecondarycolors.Lichtensteinelevated"low"cultureto"high"art,forcingviewerstoquestiontheboundariesbetweenthem.

ThegoalofPopArtwasn'tjusttomimicconsumerismbuttoanalyzeit.Itreflectedtheboomingpost-wareconomyandtheriseofaconsumeristsociety.Bypresentingfamiliarobjectsinanartisticcontext,PopArtmadetheaudiencecriticallythinkabouttheworldtheylivedin.

Questions:

1.Whatisthemainpurposeofthelecture?

A.TocompareBritishandAmericanart.

B.Toexplainthetechniquesofsilk-screening.

C.TogiveanoverviewofthePopArtmovement.

D.TodiscussthebiographyofAndyWarhol.

2.Accordingtotheprofessor,howdidAndyWarholproducehisart?

A.Byusingtraditionaloilpaintingtechniques.

B.Byusingsilk-screeningtoremovetheartist'stouch.

C.Byhand-paintingeverydetail.

D.Bysculptingsoupcansoutofclay.

3.WhydoestheprofessormentionRoyLichtenstein?

A.Toshowanotherartistwhousedcomicbookimagery.

B.TocontrasthimwithWarhol'sstyle.

C.TodiscussthehistoryofBen-Daydots.

D.Tocriticizetheuseofblackoutlines.

4.Whatdoestheprofessorimplyaboutthe"low"culturementioned?

A.ItwasconsideredunworthyofartisticattentionbeforePopArt.

B.Itwasalwaystheprimarysubjectofhistorypaintings.

C.Itreferstoclassicalmusicandopera.

D.Itwastooexpensiveformostpeople.

5.WhatwasthebroadersocialcontextofPopArt?

A.Theeconomicdepressionofthe1930s.

B.Thepost-wareconomicboomandconsumerism.

C.Thepoliticalprotestsofthe1960s.

D.Thetechnologicalrevolutionofthe1980s.

Lecture3:Geology(VolcanicHazards)

Professor:Weoftenthinkoflavaflowsasthegreatestdangerfromvolcanoes,butforpeoplelivingnearstratovolcanoes,pyroclasticflowsarefarmoredeadly.Apyroclasticflowisafast-movingcurrentofhotgasandvolcanicmatterthatmovesdowntheslopeofavolcanoatspeedsupto700km/h.Theycanreachtemperaturesofover1,000degreesCelsius.

Theseflowsarecomposedofpumice,ash,andvolcanicrocks.Thedensityoftheflowishigherthanair,sotheyhugthegroundandcaneasilytoptopographicbarrierslikevalleysorhills.Nothingintheirpathsurvives.ThehistoricaleruptionofMountVesuviusin79AD,whichdestroyedPompeii,isaclassicexamplewherepyroclasticflowscausedthemajorityoffatalities.

Anotherhazardisthelahar.Thisisatypeofmudflowordebrisflowcomposedofpyroclasticmaterial,water,androck.Laharscanoccurwhenavolcanoeruptsandmeltssnowandiceonthesummit,orwhenheavyrainfallsonloosevolcanicash.Theycantravelhundredsofkilometersdownrivervalleys,destroyingbridgesandtownsfarfromthevolcanoitself.Monitoringthesehazardsinvolvestrackingseismicactivityandgrounddeformation,butpredictionremainsaninexactscience.

Questions:

1.Whatisthemaintopicofthelecture?

A.Theformationofdifferenttypesofvolcanoes.

B.Thebenefitsofvolcanicsoil.

C.Hazardsassociatedwithstratovolcanoes,specificallypyroclasticflowsandlahars.

D.ThehistoryofMountVesuvius.

2.Accordingtotheprofessor,whyarepyroclasticflowsmoredangerousthanlavaflows?

A.Theyarehotterandfaster.

B.Theylastlonger.

C.Theyareinvisible.

D.Theycontainmorewater.

3.Howdoestheprofessorexplainthemovementofpyroclasticflows?

A.Theyrisehighintotheatmosphere.

B.Theyflowonlythroughundergroundtunnels.

C.Theymovealongthegroundduetohighdensity.

D.Theyarepushedbystrongwinds.

4.Whatisalahar?

A.Aflowofhotgasandrock.

B.Amudflowordebrisflowcontainingvolcanicmaterialandwater.

C.Atypeofearthquakecausedbymagma.

D.Acloudofvolcanicash.

5.Whatdoestheprofessorimplyaboutvolcanicprediction?

A.Itiscurrentlyimpossibletopredicteruptions.

B.Itisaninexactsciencedespitemonitoringefforts.

C.Ithaspreventedallrecentvolcanicdisasters.

D.Itreliessolelyonvisualobservation.

【SpeakingSection】

Task1(Independent)

Someuniversitystudentsprefertotakeclassesthatdirectlyrelatetotheirfuturecareers.Othersprefertotakeavarietyofcoursesindifferentsubjectstoexploredifferentinterests.Whichapproachdoyouthinkisbetterandwhy?

Task2(CampusSituation)

Reading:Theuniversityadministrationplanstoclosethecampuscoffeeshoplocatedinthestudentcenter.Theadministrationclaimsthatthecoffeeshopistooexpensivetooperateduetorisingrentcosts.Furthermore,thereisanew,largercoffeechainopeningjustacrossthestreetfromthecampus,whichwillprovidestudentswithmoreoptions.

Listening:Themandisagreeswiththeplan.

Reason1:Convenience.Thecampuscoffeeshopisrightinthecenterwherestudentshaveclasses.Goingacrossthestreettakestimeandinvolvescrossingabusyintersection,whichisdangerousandstressfulbetweenclasses.

Reason2:StudyEnvironment.Thecampusshopisaquietplacewherestudentsstudyormeetforgroupprojects.Thenewchainacrossthestreetisusuallyverynoisyandcrowded,notsuitableforacademicwork.

Task3(Acad