托福作文写作范文详解ioxid.docx

托福作文写作范文详解ReadingEthanolfuelmadefromplantssuchascornandsugarcanezhasbeenadvocatedbysomepeopleasanalternativetogasolineintheUnitedStates.However,manycriticsarguethatethanolisnotagoodreplacementforgasolineforseveralreasons.First,theincreaseduseofethanolfuelwouldnothelptosolveoneofthebiggestenvironmentalproblemscausedbygasolineuse:globalwarming.Likegasoline,ethanolreleasescarbondioxideintotheatmospherewhenitisburnedforfuelandcarbondioxideisgreenhousegas:ithelpstrapheatintheatmosphere.Thus,ethanoloffersnoenvironmentaladvantageovergasoline.Second,theproductionofsignificantamountsofethanolwoulddramaticallyreducetheamountofplantsavailableforusesotherfuel.Forexample,muchofthecornnowgrownintheUnitedStatesisusedtofeedfarmanimalssuchascowsandchickens.Itisestimatedthatifethanolwereusedtosatisfyjust10percentofthefuelneedsintheUnitedStates,morethan60percentofthecorncurrentlygrownintheunitedstatedwouldhavetobeusedtoproduceethanol.Ifmostofthecornwereusedtoproduceethanolzasubstantialsourceoffoodforanimalswoulddisappear.Third,ethanolfuelwillneverbeabletocompetewithgasolineonprice.Althoughthepricesofethanolandgasolinefortheconsumerarecurrentlyaboutthesame,thisisonlybecauseofthehelpintheformoftaxsubsidiesgiventoethanolproducersbytheUnitedStatesgovernment.ThesetaxsubsidieshavecosttheUnitedStatesgovernmentover$11billioninthepast30years.IftheUnitedStatesgovernmentweretostophelpingproducersinthiswayzthepriceofethanolwouldincreasegreatly.ListeningEthanolactuallyisagoodalternativetogasoline,althoughyoujustreadthreereasonswhyitsnotagoodalternative,notoneofthesethreereasonsisconvincing.First,theincreaseduseofEthanolfuelwillnotaddtoglobalwarming.It,struethat,whenEthanolisburned,itreleasescarbondioxideintotheatmosphere,butasyouread,Ethanolisoftenmadefromplantssuchascorn.Well,theprocessofgrowingtheplantscounteractsthisreleaseofcarbondioxide.Letmeexplain.Everygrowingplantabsorbscarbondioxidefromtheairaspartofitsnutrition.SogrowingplantsforEthanolproductionactuallyremovescarbondioxidefromtheatmosphere.Second,largescaleproductionofEthanoldoesn,thavetoreducethesourcesoffoodforanimals.That,sbecausewecanproduceEthanolusingcellulose,celluloseisthemaincomponentofplants,cellwalls,andyou,llfindmostcelluloseinthosepartsofplantsthatarenoteatenbyanimals.SozsincewecanproduceEthanolfromtheplantpartsthataren,teaten,theamountofanimalfeedthatisavailablewillnotbereduced.Third,inthefuture,Ethanolwillbeabletocompetewithgasolineintermsofprice.ItstruethatgovernmentsubsidiesmakeEthanolcheaperthanitwouldnormallybe,butthissupportwon,talwaysbeneeded.OnceenoughpeoplestartbuyingEthanoLEthanolproducerswillincreasetheirproductionofEthanol.Generally,increasedproductionofproductsleadstoadropinitsprice.SothepriceofEthanolwillgodownasmoreofitbecomesavailable.Studiesshowthat,ifEthanolproductioncouldbethreetimesgreaterthanitisnowzthecostofproducingaunitofEthanolwilldropbyfortypercent一、阅读听力要点概括ReadingPassageMainpoints:ManyCriticsthinkethanolisnotagoodreplacementforgasoline.Subpoint1:EthanolemitsCO2whenitburnsandhasnoadvantagetoenvironment.Subpoint2:Productionofethanolcutsenergysupplytofood.Subpoint3:Ethanolpricewouldincreaseifgovernmentstopssubsidies.LectureAttitude:Notconvincing.SubPoint1:GrowingplantsabsorbsCO2soitremovesCO2fromatmosphere.SubPoint2:Ethanolisproduceusingpartsthataren,teaten.(Cellulose,mainofplants)SubPoint3:Ethanolcancompetewithgasinpriceinthefuture.(Increaseleadsdropinprice.)二、范文逐段赏析Paragraph1Thelecturerrefutesalltheevidenceinthereadingpassage,whichevidenceseemstoaffirmthereareexistingshortagesofethanol.Healsoholdsthatethanolisquitelikelyagoodreplacementofgasolineasafuturefuel.此段功能：（Listeningpassage后文提到用L代替）（Readingpassage后文用R代替）以L为根本，L觉得R的证据和观点都不可信，作者用了一个同义词refute（驳倒）,L驳倒了R的所有证据，觉得酒精是一个非常好的汽油代替品。此段结构：首段第一句话以L出发，L反对R的所有并复述R的观点。第二句复述L的观点，使读者知道L准备要反驳的点。Paragraph2First,theapplicationofethanolwillnotcreateasmuchheatastheuseofgasoline.Althoughtheburningofethanolalsogeneratescarbondioxide,itwillnotsignificantlyaddtotheseverityofglobalwarming.Sincetheproductionofethanolrequirestheplantingandharvestingofcorn,whichgrowthinturnrequirescarbondioxideasnutrition,theheightenedamountofunwantedgaswillbeoffsettherewith.Thisisthesituationforwhichthereadingdoesn'taccount.此段功能：引出第一个分论点，说大面积应用酒精并不会造成太多温室效应。因为酒精的种植过程会吸收很多二氧化碳。R中没提到这个吸收过程，L就攻击了这个点。此段结构：此段为总分结构，先列举L的观点，酒精不会产生那么多温室气体。然后就开始写L的证据，最后告诉读者，刚才举的证据恰好是R没想到的，R证据不足。Paragraph3Second,theproductionofethanoldoesn'treducethefoodsupplyforfarmanimals.Becauseethanolcanbemadeoutofanypartoftheplantcellwalls,whichcontaincellulose,thecostofusingtheplants'usefulpartscanbeavoided.Thisadvantagerenderstheworryofthereadingtotallyunnecessary.此段功能:引出第二个分论点，酒精制造是不会减少家禽的食物供给。因为酒精是使用不可作为食料的包含纤维素的植物细胞做的。R中提到的忧虑是毫无必要的。此段结构：此段为总分结构。先确立L的观点（不会减少食物供给），再给解释，最后说这个优势显得R的忧虑无必要，从而达到了驳到R的地步。Paragraph4Finally,thepriceofethanolwillbelargelyreducedifthescaleofmanufactureincreases.Accordingtostatistics,ifthemanufacturescale,followingheavierdemandofconsumers,canbeenlargedbythreetimeszitscostwillbereducedbyfortypercent.Undersuchcircumstance,thegovernmentsubsidiesmentionedinthereadingwouldnolongerbeneeded.此段功能：引出第三个分论点。在价格的竞争力上，L的总结是，大规模制造酒精会使成本大量下降。随后列举了具体数字，在具体数字的验证下，原先担心的政府停止资助导致酒精价格飙升这种事情是不需要担心了。此段结构:此段为总分结构。首先复述表明L的观点，然后列举支撑L的例子或数字，最后为总体逻辑服务，说R的观点notConvincingo三、范文全篇总评1、逻辑结构全文遵从逻辑总分结构，第一段复述了双方的观点并且表明了L对R的态度，随后三个论段依次展开。每段中L提出新的证据，新的解释，最后一一驳倒R的观点。2、语言表达文中偏难词不多，但用在了一些非常有创意的表达方法，可以借鉴的有:1. affirm：证实confirmverifyIaffirmwhathesaidisture.2. addtotheseverityof:增加了（某事件）的严重性3. Thisadvantagerenderstheworryofthereadingtotallyunnecessary.Render：渲染，表现ProvidedeclareThepowerofoceanisbeautifullyrenderedinthispoem.