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第一部分真题精选及详解[听力音频]

新托福考试真题精选及详解（一）

ReadingSection

Directions

TheReadingsectiontestsyourabilitytounderstandreadingpassageslikethoseincollegetextbooks.Thepassagesareabout700wordsinlength.

ThisistheshortformatfortheReadingsection.Ontheshortformat,youwillreadthreepassages.Aftereachpassage,youwillanswer12-14questionsaboutit.Youmaytakenoteswhileyouread,butnotesarenotgraded.Youmayuseyournotestoanswerthequestions.Somepassagesmayincludeawordorphrasethatisunderlinedinblue.Clickonthewordorphrasetoseeaglossarydefinitionorexplanation.

Choosethebestanswerformultiple-choicequestions.Followthedirectionsonthepageoronthescreenforcomputer-assistedquestions.Mostquestionsareworth1point,butthelastquestionineachpassageisworthmorethan1point.

TheReadingsectionisdividedintoparts.ClickonNexttogotothenextquestion.ClickonBacktoreturntopreviousquestions.Youmayreturntopreviousquestionsforallofthepassagesinthesamepart,butafteryougotothenextpart,youwillnotbeabletoreturntopassagesinthepreviouspart.BesurethatyouhaveansweredallofthequestionsforthepassagesineachpartbeforeyouclickonNextattheendofthepassagetomovetothenextpart.

YoucanclickonReviewtoseeachartofthequestionsyouhaveansweredandthequestionsyouhavenotansweredineachpart.Fromthisscreen,youcanreturntothequestionyouwanttoanswerinthepartthatisopen.

Youwillhave20minutestoreadeachpassageandanswerthequestionsforthatpassage.Youwillhave60minutestocompleteallofthepassagesandanswerallofthequestionsontheshortformat.AclockonthescreenwillshowyouhowmuchtimeyouhavetocompletetheReadingsection.

THEDEVELOPMENTOFREFRIGERATION

[1]Coldstorage,orrefrigeration,iskeepingfoodattemperaturesbetween32and45degreesFinordertodelaythegrowthofmicroorganisms—bacteria,molds,andyeast—thatcausefoodtospoil.Refrigerationproducesfewchangesinfood,someats,fish,eggs,milk,fruits,andvegetableskeeptheiroriginalflavor,color,andnutrition.Beforeartificialrefrigerationwasinvented,peoplestoredperishablefoodwithiceorsnowtolengthenitsstoragetime.Preservingfoodbykeepingitinanice-filledpitisa4,000-year-oldart.Coldstorageareaswerebuiltinbasements,cellars,orcaves,linedwithwoodorstraw,andpackedwithice.Theicewastransportedfrommountains,orharvestedfromlocallakesorrivers,anddeliveredinlargeblockstohomesandbusinesses.

[2]Artificialrefrigerationistheprocessofremovingheatfromasubstance,container,or,enclosedarea,toloweritstemperature.Theheatismovedfromtheinsideofthecontainertotheoutside.Arefrigeratorusestheevaporationofavolatileliquid,orrefrigerant,toabsorbheat.Inmosttypesofrefrigerators,therefrigerantiscompressed,pumpedthroughapipe,andallowedtovaporize.Astheliquidturnstovapor,itlosesheatandgetscolderbecausethemoleculesofvaporuseenergytoleavetheliquid.Themoleculesleftbehindhavelessenergyandsotheliquidbecomescolder.Thus,theairinsidetherefrigeratorischilled.

[3]Scientistsandinventorsfromaroundtheworlddevelopedartificialrefrigerationduringtheeighteenthandnineteenthcenturies.WilliamCullendemonstratedartificialrefrigerationinScotlandin1748,whenheletethyletherboilintoapartialvacuum.In1805,AmericaninventorOliverEvansdesignedthefirstrefrigerationmachinethatusedvaporinsteadofliquid.In1842,physicianJohnGorrieusedEvans’sdesigntocreateanair-coolingapparatustotreatyellow-feverpatientsinaFloridahospital.Gorrielaterlefthismedicalpracticeandexperimentedwithicemaking,andin1851hewasgrantedthefirstU.S.patentformechanicalrefrigeration.Inthesameyear,anAustralianprinter,JamesHarrison,builtanetherrefrigeratorafternoticingthatwhenhecleanedhistypewithetheritbecameverycoldastheetherevaporated.Fiveyearslater,Harrisonintroducedvapor-compressionrefrigerationtothebrewingandmeatpackingindustries.

[4]BrewingwasthefirstindustryintheUnitedStatestousemechanicalrefrigerationextensively,andinthe1870s,commercialrefrigerationwasprimarilydirectedatbreweries.German-bornAdolphusBuschwasthefirsttouseartificialrefrigerationathisbreweryinSt.Louis.Beforerefrigeration,brewersstoredtheirbeerincaves,andproductionwasconstrainedbytheamountofavailablecavespace.Brewingwasstrictlyalocalbusiness,sincebeerwashighlyperishableandshippingitanydistancewouldresultinspoilage.Buschsolvedthestorageproblemwiththecommercialvapor-compressionrefrigerator.Hesolvedtheshippingproblemwiththenewlyinventedrefrigeratedrailcar,whichwasinsulatedwithicebunkersineachend.Aircameinonthetop,passedthroughthebunkers,andcirculatedthroughthecarbygravity.InsolvingBusch’sspoilageandstorageproblems,refrigerationalsorevolutionizedanentireindustry.By1891,nearlyeverybrewerywasequippedwithmechanicalrefrigeratingmachines.

[5]Therefrigeratorsoftodayrelyonthesamebasicprincipleofcoolingcausedbytherapidevaporationandexpansionofgases.Until1929,refrigeratorsusedtoxicgases—ammonia,methylchloride,andsulfurdioxide—asrefrigerants.Afterthosegasesaccidentallykilledseveralpeople,chlorofluorocarbons(CFCs)becamethestandardrefrigerant.However,theywerefoundtobeharmfultotheearth’sozonelayer,sorefrigeratorsnowusearefrigerantcalledHFC134a,whichislessharmfultotheozone.

1.Whatisthemainreasonthatpeopledevelopedmethodsofrefrigeration?

(A)Theywantedtoimprovetheflavorandnutritionalvalueoffood.

(B)Theyneededtoslowthenaturalprocessesthatcausefoodtospoil.

(C)Theyneededausefortheicethatformedonlakesandrivers.

(D)Theywantedtoexpandtheproductionofcertainindustries.

2.Thewordperishableinparagraph1isclosestinmeaningto

(A)capableofspoiling

(B)uncooked

(C)ofanimalorigin

(D)highlynutritious

3.Whatcanbeinferredfromparagraph1aboutcoldstoragebeforetheinventionofartificialrefrigeration?

(A)Itkeptfoodcoldforonlyaboutaweek.

(B)Itwasdependentonasourceoficeorsnow.

(C)Itrequiredacontainermadeofmetalorwood.

(D)Itwasnotasafemethodofpreservingmeat.

4.ArtificialrefrigerationinvolvesallofthefollowingprocessesEXCEPT

(A)thepumpingofwatervaporthroughapipe

(B)therapidexpansionofcertaingases

(C)theevaporationofavolatileliquid

(D)thetransferofheatfromoneplacetoanother

5.Whichsentencebelowbestexpressestheessentialinformationinthehighlightedsentenceinparagraph2?Incorrectchoiceschangethemeaninginimportantwaysorleaveoutessentialinformation.

(A)Ittakesalotofenergytotransformaliquidintoavapor,especiallywhenthevaporlosesheat.

(B)Somegasesexpandrapidlyandgiveoffenergywhentheyencounteraverycoldliquid.

(C)Whenkineticenergyischangedtoheatenergy,liquidmoleculesturnintovapormolecules.

(D)Duringevaporation,thevapormoleculesuseenergy,andtheliquidbecomescolder.

6.Accordingtothepassage,whowasthefirstpersontouseartificialrefrigerationforapracticalpurpose?

(A)WilliamCullen

(B)OliverEvans

(C)JohnGorrie

(D)AdolphusBusch

7.Theworditinparagraph3refersto

(A)printer

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文章到此结束，如果本次分享的新托福真题和2020年新托福题库的问题解决了您的问题，那么我们由衷的感到高兴！