概念英语英语第四册课本教学材料整编

新概念英语第四册课文fromwhichhisfriendwassuffering,andofwhathadpreviouslybeenwrongwithhiswife,butamedicinethathadworkedsowellinoneformofillnesswouldsurelybeofequalbenefitinanother,andcomfortedbythethoughtofthehelphewasbringingtohisfriend,hehastenedtoHenryTaylor'shouse.Historydoesnotrelatewhetherhisfriendacceptedhismedicalhelp,butinallprobabilityhedid.Thegreatadvantageoftakingmedicineisthatitmakesnodemandsonthetakerbeyondthatofputtingupforamomentwithadisgustingtaste,andthatiswhatallpatientsdemandoftheirdoctors--tobecuredatnoinconveniencetothemselves.Lesson35Manystrangenewmeansoftransporthavebeendevelopedinourcentury,thestrangestofthembeingperhapsthehovercraft.In1953,aformerelectronicsengineerinhisfifties,ChristopherCockerell,whohadturnedtoboat-buildingontheNorfolkBroads,suggestedanideaonwhichhehadbeenworkingformanyyearstotheBritishGovernmentandindustrialcircles.Itwastheideaofsupportingacraftona'pad',orcushion,oflow-pressureair,ringedwithacurtainofhigherpressureair.Eversince,peoplehavehaddifficultyindecidingwhetherthecraftshouldberangedamongships,planes,orlandvehicles--foritissomethinginbetweenaboatandanaircraft.Asashipbuilder,Cockerellwastryingtofindasolutiontotheproblemofthewaveresistancewhichwastesagooddealofasurfaceship'spowerandlimitsitsspeed.Hisanswerwastoliftthevesseloutofthewaterbymakingitrideonacushionofair,nomorethanoneortwofeetthick.Thisisdonebyagreatnumberofring-shapedairjetsonthebottom36新概念英语第四册课文ofthecraft.It'flies',therefore,butitcannotflyhigher--itsactionde-pendsonthesurface,waterorground,overwhichitrides.ThefirsttestsontheSolentin1959causedasensation.Thehovercrafttravelledfirstoverthewater,thenmountedthebeach,climbedupthedunes,andsatdownonaroad.LateritcrossedtheChannel,ridingsmoothlyoverthewaves,whichpresentednoproblem.Sincethattime,varioustypesofhovercrafthaveappearedandtakenupregularservice--cruisesontheThamesinLondon,forinstance,havebecomeanannualattraction.Butweareonlyatthebeginningofadevelopmentthatmaytransportnet-seaandlandtransport.ChristopherCockerell'scraftcanestablishtransportworksinlargeareaswithpoorcommunicationssuchasAfricaorAustralia;itcanbecomea'flyingfruit-bowl',carryingbananasfromtheplantationstotheports,gianthovercraftlinerscouldspantheAtlantic;andtherailwayofthefuturemaywellbethe'hovertrain',ridingonitsaircushionoverasinglerail,whichitnevertouches,atspeedsupto300m.p.h.--thepossibilitiesappearunlimited.Lesson36Ourknowledgeoftheoceansahundredyearsagowasconfinedtothetwo-dimensionalshapeofthesea-surfaceandthehazardsofnavigationpresentedbytheirregularitiesindepthoftheshallowwaterclosetotheland.Theopenseawasdeepandmysterious,andanyonewhogavemorethanapassingthoughttothebottomconfinesofthe37新概念英语第四册课文oceansprobablyassumedthatthesea-bedwasflat.SirJamesClarkRosshadobtainedasoundingofover2,400fathomsin1836butitwasnotuntil1800,whenH.M.S.PorcupinewasputatthedisposaloftheRoyalSocietyforseveralcruises,thataseriesofdeepsoundingswasobtainedintheAtlanticandthefirstsampleswerecollectedbydredgingthebottom.ShortlyafterthisthefamousH.M.S.Challengerexpeditionestablishedthestudyofthesea-floorasasubjectworthyofthemostqualifiedphysicistsandgeologists.AburstofactivityassociatedwiththelayingofsubmarinecablessoonconfirmedtheChallenger'sobservationthatmanypartsoftheoceanweretwotothreemilesdeep,andtheexistenceofunderwaterfeaturesofconsiderablemagnitude.TodayenoughsoundingsareavailabletoenableareliefmapoftheAtlantictobedrawnandweknowsomethingofthegreatvarietyofthesea-bed'stopography.Sincetheseacoversthegreaterpartoftheearth'ssurfaceitisquitereasonabletoregardthesea-floorasthebasicformofthecrustoftheearth,withsuperimposeduponitthecontinents,togetherwiththeislandsandotherfeaturesoftheoceans.Thecontinentsformruggedtablelandswhichstandnearlythreemilesabovetheflooroftheopenocean.Fromtheshore-lineouttoadistancewhichmaybeanywherefromafewmilestoafewhundredmilesrunsthegentleslopeofthecontinentalshelf,geologicallypartofthecontinents.Therealdividing-linebetweencontinentsandoceansoccursatthefootofasteeperslope.Thiscontinentalslopeusuallystartsataplacesomewhereneartheice-fathommarkandinthecourseofafewhundredmilesreachesthetrueocean-floorat2,500-3,000fathoms.Theslopeaverages38新概念英语第四册课文about1in30,butcontainssteep,probablyvertical,cliffs,andgentlesediment-coveredterraces,andnearitslowerreachesthereisalongtailing-offwhichisalmostcertainlytheresultofmaterialtransportedouttodeepwaterafterbeingerodedfromthecontinentalmasses.Lesson37TheVictorians,realizingthatthegreatesthappinessaccordedtomanisthatprovidedbyahappymarriage,endeavouredtopretendthatalltheirmarriageswerehappy.We,forourpart,admittingthefactthatnofeatofintelligenceandcharacterissoexactingasthatrequiredoftwopeoplewhodesiretolivepermanentlytogetheronabasisofamity,areobsessedbytheproblemofhowtorenderthebasicfactsofcohabitationsimplerandmorereasonable,inorderthatunhappymarriagesmaylessfrequentlyresult.TheVictorianswouldhaveconsideredit'painful'or'unpleasant'wereonetopointoutthatonlyfourmarriagesoutofeverytenareanythingbutforcedservitudes.Weourselvesstartfromthisveryassumptionandtrytobuildfromitatheoryofmoresensiblerelationsbetweenthesexes.OfallformsofarrantuntruthfulnessVictorianoptimismappearstometohavebeenthemostcowardlyandthemostdamaging.Truth,therefore,isanattitudeofthemind.Itisimportant,ifonedoesnotwishtoinconvenienceandtoboreone'sfriends,nottotelllies.Butitismoreimportantnottothinklies,ortoslideintothosemechanicalanduntruthfulhabitsofthoughtwhicharesopleasantandsoeasyasdescentstomentalineptitude.Thevictorianhabitofmind39新概念英语第四册课文(whichIconsidertohavebeenabadhabitofmind)wasundulypreoccupiedbywhatwassociallyandmorallyconvenient.Convenienceis,however,inallaffairsoflife,anexecrabletestofvalue.Oneshouldhavethecouragetothinkuncomfortably,sinceitisonlybyrejectingtheconvenientthatonecancometothinkthetruth.Not,afterall,thatthereisanysuchthingastruth.Atbestwecanapproachtosomerelativeapproximation.Ontheotherhand,thereissurelysuchathingasuntruth.Oneisgenerallyawarewhenonehassaidsomething,oractedinsomewaywhichhasleftonotherpeopleanimpressionnotstrictlyinaccordancewiththefacts.Oneisgenerallyaware,also.whenonehasthrustasideaninconvenientthoughtandslidintoitsplaceanotherthoughtwhichisconvenient.One'sawarenessintheformercaseisingeneralmoreacutethaninthelatter,sincewearemoreonthelook-outfortheliesweutterthanforthosewemerelythink.Infact,however,itistheuntruthfulthoughtwhichisthemoreviciousofthetwo.Spokenliesareinvariablytiresomeandmayactuallybedishonest.Butcontinuouslyinginthemind,adiseasetowhichtheAnglo-Saxonispeculiarlyexposed,spellsthedestructionofhumanthoughtandcharacter.Lesson38Appreciationofsculpturedependsupontheabi8litytorespondtoforminthreedimensions.Thatisperhapswhysculpturehasbeendescribedasthemostdifficultofallarts;certainlyitismoredifficultthantheartswhichinvolveappreciationofflatforms,shapeinonlytwodimensions.Manymorepeopleare'form-blind'thancolour-blind.Thechildlearningtosee,firstdistinguishesonlytwo-dimensionalshape;itcannotjudge40