《汽車專業(yè)英語》課件第1章

PARTIHISTORYOFAUTO1.1EarlyAdventureswiththeAutomobile1.2TheBirthofAutomobilesPART?Ⅰ

HISTORYOFAUTO學習目標通過本章的學習，你應當能夠：了解汽車的歷史、汽車的典故和汽車的相關(guān)知識，掌握有關(guān)詞匯、詞組。掌握汽車英語的習慣表達方法。能查閱與汽車知識有關(guān)的英文資料。能借助字典翻譯汽車歷史方面的文章。1.1EarlyAdventureswiththeAutomobile

The“horselesscarriage”madeitsdebutatChicago’sColumbianExpositionin1893.Crude,nomorethanatwo-seatedbuckboardpoweredbyanelectricmotor,none-the-lesstheexhibitexciteditsaudience.Withinfifteenyearstheautomobileindustrywasfirmlyestablished,producingroomy,comfortablecarscapableoftravelingsixtymilesperhour.Firstseenasatoyfortherich,thecarbegantobetakenmoreseriouslyasitsadvantagesoverthehorsebecameobvious.

Drivingintheseearlydayswasalwaysachallenge.Dirtroadsthatthehorsefoundperfectlyacceptablebecameimpassablequagmiresofmudfortheautomobile.Nogasstationsdottedtheroadscape.

Despitethesechallenges,itwasnotlongbeforetheautomobiletransformeditselffromnoveltytonecessity.Althoughmanywouldcontinuetocriticizethis“newfangled”modeoftransportation,onethingwascertain:therewouldbenoturningback.TheautomobilebecameafixtureofAmericancultureandourinfatuationwiththecarblossomedintoaloveaffair.WinningtheVanderbiltCup,1906

In1904,W.K.Vanderbilt,establishedthe“VanderbiltCup”topromotethesportofautomobileracing.TheeventwasoriginallyrunonLongIslandoverpublicroads.Crowdslinedtheracewaywithoutbenefitofanybarriers.Driversbegantheraceattimedintervalswiththefirsttocrossthefinishinthefastesttimedeclaredthewinner.In1906,LouisWagnerwontheracedrivingaDarracq.MotoringtoVirginia,1907

In1907,anintrepidgroupofadventurersdrovefromNewYorkCitytoJamestown,VirginiatoattendtheJamestownExposition.TheirjourneylastedthreedaysandtookthemthroughNewYork,Pennsylvania,Delaware,MarylandandVirginia.AliceRamsey,firstwomantodrivecoast-to-coast,1909(SeeFig.1.1.1)NelsonJacksonwasthefirsttomotorcoast-to-coastin1903.Twodozenotherpioneersmatchedhisfeatoverthenextfiveyears,butnonewasawoman.ThishonorfelltoAliceHuylerRamseya22-year-oldhousewifeandmotherfromHackensack,NewJersey.OnJune9,1909,Alice,andthreewomencompanions(noneofwhomdrove),leftManhattan.Fifty-ninedaysand3,800mileslatertheyarrivedinSanFrancisco.Fig.1.1.2showsustheroute.AliceRamsey,hercrew(NettiePowell,MargaretAtwoodandHermineJans)andherMaxwellFig.1.1.1FirstWomentoDriveAliceRamsey’sRoute;noroadmaps,fewpavedroads,fewroadsatallwestoftheMississippi.Fig.1.1.2Route“FourmilesfromGrandIslandtherearaxlebrokeagain.AfarmfamilytookusinwhileamechanicfromDenverbroughtanother.NettiewashappytogiveherplacetothemechanicandridethetrainaheadtoCheyenne.NearOgallala,Nebraska,wewerehaltedbyanondescriptsheriff’sposseonhorseback.Theywerelookingfortwomurderersandatfirstdidn’tbelieveuswhenweexplainedthatwewereonlytryingtodrivefromNewYorktoSanFrancisco.Itwasnotuntilthelawmenwereconvincedthatnofirearmsorsuspectswereconcealedthattheyallowedustogoon.”“InUtahwehitaprairiedogholeintheroadwithsuchforcethatatieboltcameoutofthetierodconnectingthefrontwheels.WehadapilotcarwithusanddriverFrankIrvingwentbacktoOrr’sranchandwewereabletomaketemporaryrepairs.Inspiteofeverything,wefinallymadeitacrossNevadaarrivingnearmidnightattheRiversideHotelinReno.NextdaywecontinuedbywayofCarsonCityacrosstheSierrastoPlaceville,thentoSacramento.”注：此篇文章出自www.EyewitnesstoH。TechnicalWords

challenge n.;vt. 挑戰(zhàn)；向……挑戰(zhàn)

impassable adj. 不能通行的,無路可通的

quagmire n. 沼澤,濕地

loveaffair n. 強烈愛好

racing vi.;adj.競賽，賽馬；賽車，比賽的

raceway n. 水溝,(賽車用的)跑道

barrier n. (阻礙通道的)障礙物,柵欄,屏障

adventurer n. 冒險家

coast-to-coast adj. 由大西洋岸至太平洋岸的

axle n. 輪軸,車軸

mechanic n. 技工,機修工,機械師PhrasesandExpressions

tiebolt 連接螺栓

tierod 轉(zhuǎn)向橫拉桿

pilotcar 先驅(qū)車NotesontheText

1．Crude,nomorethanatwo-seatedbuckboardpoweredbyanelectricmotor,none-the-lesstheexhibitexciteditsaudience.樸實的不超過兩座的四輪馬車用一臺電動發(fā)動機作為動力，這樣的陳列品依然使觀眾興奮異常。

2．Dirtroadsthatthehorsefoundperfectlyacceptablebecameimpassablequagmiresofmudfortheautomobile.馬匹完全可以行走的泥濘路面對汽車來說變成了難以通行的沼澤地。

3．In1904,W.K.Vanderbilt,establishedthe“VanderbiltCup”topromotethesportofautomobileracing.

1904年，W.K.范德比爾特（W.K.Vanderbilt）創(chuàng)立了“范德比爾特杯”以促進汽車比賽運動的發(fā)展。

4．NelsonJacksonwasthefirsttomotorcoast-to-coastin1903.

1903年，納爾遜·杰克遜（NelsonJackson）第一個駕車從大西洋岸到太平洋岸。

5．AfarmfamilytookusinwhileamechanicfromDenverbroughtanother.NettiewashappytogiveherplacetothemechanicandridethetrainaheadtoCheyenne.NearOgallala,Nebraska,wewerehaltedbyanondescriptsheriff’sposseonhorseback.Theywerelookingfortwomurderersandatfirstdidn’tbelieveuswhenweexplainedthatwewereonlytryingtodrivefromNewYorktoSanFrancisco.一個農(nóng)民家庭接待了我們，一名機修工從丹佛（Denver）帶來了一根新的后軸。內(nèi)蒂(Nettie)樂意地把她的位置讓給了這個機修工，自己乘火車先行去塞延（Cheyenne）。在內(nèi)布拉斯加州（Nebraska）Ogallala，我們被一隊莫名其妙的郡治安官人馬阻止了。他們正在尋找2個殺人犯，我們解釋我們只是想駕車從紐約到舊金山。Exercises

Ⅰ.?AnswerthefollowingquestionsinEnglish.

1．WhatmadeitsdebutatChicago’sColumbianExpositionin1893?

2．WhatbecameafixtureofAmericancultureandourinfatuationwiththecarblossomedintoaloveaffair?

3．WhendidAlice,andthreewomencompanions(noneofwhomdrove),leaveManhattan?

4．Whywerewehaltedbyanondescriptsheriff’sposseonhorseback?

5．InUtahdidwehitaprairiedogholeintheroadwithsuchforcethatatieboltcameoutofthetierodconnectingthefrontwheels?

Ⅱ.?TranslatefollowingexpressionsintoEnglish.

1．加油站

2．新鮮事物

3．往回走，折轉(zhuǎn)

4．汽車比賽

5．轉(zhuǎn)向橫拉桿

6．大西洋岸至太平洋岸

Ⅲ.?TranslatefollowingsentencesintoEnglish.

1．15年內(nèi)，汽車工業(yè)已經(jīng)站穩(wěn)腳跟。

2．道路上沒有星羅棋布的加油站。

3．汽車還是由新奇事物變?yōu)楸匦杵贰?/p>

4．汽車成為美國文化的固有事物。

5．1903年，杰克遜是駕車從大西洋岸到太平洋岸的第一人。

6．經(jīng)歷了59天和3?800英里之后，她們到達了舊金山。

Ⅳ.?Studythefollowinglistandname.*

1．linearspeed,linearvelocity,angularspeed,angularvelocity,peripheralspeed,peripheral,rotationalspeed,rotationalvelocity

2．a(chǎn)llowablespeed,admissiblevelocity,criticalspeed,criticalvelocity,maximumspeed,effectivetopspeed

3．uniformspeed,uniformvelocity,stablespeed,constantspeed,slipvelociy,minimumspeed(ingear),maximumspeed(ingear)ReadingMaterialToyotaCorollaHistory

TherearwheeldriveToyotaCorollawasfirstintroducedinJapaninmodelyear1966.

Twoyearslater,itwasbroughttotheUnitedStates,replacingtheunpopularandbarely-noticedCrown.

Itlastedonlytwoyearswithitsoriginal1.1literengine,whenalarger1970modelappeared,poweredbya“muchlarger”1.2literengine.Thisnewmodelactuallybecamethesecondbestsellingimportcarin1970.Thenextyear,1971,broughta1.6literengine,moreintunewithAmericantastes.

1974sawthethirdgeneration,andtheCorolla’sstrongestpopularity-includingtheinexpensiveCorollaTercelmodel,itwasthebest-sellingvehicleintheworldfrom1974to1977.Fiveyearslater,in1979,afourthgenerationappeared,stillwithrearwheeldrive.Thiswastolastuntil1984,whenthefifthgenerationCorollacamewithfrontwheeldriveandacoupeversion,theGT-S,witha16valveengine.TheGT-Sremainedinproductionthrough1991.

Facedwithincreasingsales,ToyotaenteredajointventurewithGeneralMotorstocreateNUMMI.NUMMItookoveraratheratrociousGeneralMotorsplantinCaliforniaandturneditintooneofthehighestqualityplantsinNorthAmerica.TheNUMMIplantbuiltboththeCorollaandtheGeneralMotorsversion,theNova(latertoberenamedPrizm).

ThesportyFXwasintroducedin1987,followedbythesixthgenerationin1988.Withsalesstillrising,ToyotaopenedanewfacilityinCanadawhichalsoproducedCorollas.In1993,theCorollamovedtoitscurrentcompactsize,garneringmanyawards.TheTercelwassplitoffasaseparatesubcompactmodeltoattractthosewhocouldnolongeraffordtheincreasinglyupscaleCorolla.A1.6literenginewasstandard,withanoptional1.8literengine.Adriver’ssideairbagwasstandard,andapassengerairbagwasaddedin1994.

By1997,allCorollassoldintheUnitedStateswerebuiltinNorthAmerica.Thewagonwasdiscontinued,butside-impactprotectionwasincreased.

In1998,thecurrentgenerationwascreated.Itsdistinguishingfeaturewasanew1.8literenginewhichproducedabout120hp.Thisengine,evenbeforeitreceivedvariablevalvetiming,waspeppyenoughtofeelmorepowerfulineverydaydrivingthanthe132hpDodgeNeonengine.Yet,itachievedverygoodgasmileageandwasquitequiet.

In2000,the1.8literenginewasgivenvariablevalvetimingforbettergasmileageandmorepower.Italsoreducedemissions,sothattheCorollacouldbecertifiedbytheEPAasalowemissionvehicle.

2001sawaminorface-liftofthesheetmetal,makingtheCorollalookevenmorelikeaCamry.Inthethirtyyearssinceitsintroduction,Corollahassoldmorecarsworldwidethananyothernameplate!1.2TheBirthofAutomobiles

Thehistoryoftheautomobileactuallybeganabout4,000yearsagowhenthefirstwheelwasusedfortransportationinIndia.SeveralItaliansrecordeddesignsforwind-drivenvehicles.ThefirstwasGuidodaVigevanoin1335.Itwasawindmill-typedrivetogearsandthustowheels.LaterLeonardodaVincidesignedclockwork-driventricyclewithtillersteeringandadifferentialmechanismbetweentherearwheels.

Intheearly15thcentury,thePortuguesearrivedinChinaandtheinteractionofthetwoculturesledtoavarietyofnewtechnologies,includingthecreationofawheelthatturnedunderitsownpower.Bythe1600s,smallsteam-poweredenginemodelsweredeveloped.

ACatholicpriestnamedFatherFerdinanVerbiestiscreditedtohavebuiltasteam-poweredvehiclefortheChineseEmperorChienLunginabout1678.Thereisnoinformationaboutthevehicle,onlytheevent.JamesWattdidn’tinventthesteamengineuntil1705.

Althoughbythemid-15thcenturytheideaofaself-propelledvehiclehadbeenputintopracticewiththedevelopmentofexperimentalvehiclespoweredbymeansofsprings,clockworks,andthewind,Nicolas-JosephCugnotofFranceisconsideredtohavebuiltthefirsttrueautomobilein1769.DesignedbyCugnotandconstructedbyM.Brezin,itisalsothefirstvehicletomoveunderitsownpowerforwhichthereisarecord.Cugnot’sthree-wheeledsteam-poweredvehiclecarriedfourpersons.Ithadatopspeedofalittlemorethan3.2km/h(2mph).

EvanswasthefirstAmericanwhoobtainedapatentfor“aself-propelledcarriage.”He,infact,attemptedtocreateatwo-in-onecombinationofasteamwagonandaflat-bottomedboat,whichdidn’treceiveanyattentioninthosedays.Duringthe1830’s,thesteamvehiclehadmadegreatadvances.ButstiffcompetitionfromrailwaycompaniesandlegislationsinBritainforcedthepoorsteamvehiclegraduallyoutofuseonroads.Theearlysteam-poweredvehiclesweresoheavythattheywereonlypracticalonaperfectlyflatsurfaceasstrongasiron.Aroadthusmadeoutofironrailsbecamethenormforthenexthundredandtwenty-fiveyears.Thevehiclesgotbiggerandheavierandmorepowerfulandassuchtheywereeventuallycapableofpullingatrainofmanycarsfilledwithfreightandpassengers.

CarlBenzandGottliebDaimler,bothGermans,sharethecreditofchangingthetransporthabitsoftheworld,fortheireffortslaidthefoundationofthegreatmotorindustryasweknowittoday.First,CarlBenzinventedthepetrolenginein1885andayearlaterDaimlermadeacardrivenbymotorofhisowndesign.Daimler’sengineprovedtobeagreatsuccessbecauseofitslessweightthatcoulddeliver1,000rpmandneededonlyverysmallandlightvehiclestocarrythem.

Francetoohadjoinedthemotoringscenarioby1890whentwoFrenchmenPanhardandLevassorbeganproducingvehiclespoweredbyDaimlerengine,andDaimlerhimself,possessedbytheautomobilespirit,wentonaddingnewfeaturestohisengine.HebuiltthefirstV-Twinenginewithaglowingplatinumtubetoexplodethecylindergas－theveryearliestformofsparkingplug.

Formanyyearsaftertheintroductionofautomobiles,threekindsofpowersourceswereincommonuse:steamengines,gasolineorpetrolengines,andelectricmotors.In1900,over2,300automobileswereregisteredinNewYork,Boston,Massachusetts,andChicago.Ofthese,1,170weresteamcars,800wereelectriccars,andonly400weregasolinecars.

Intenyearsfromtheinventionofthepetrolengine,themotorcarhadevolveditselfintoamazingdesignsandshapes.By1898,therewere50automobile-manufacturingcompaniesintheUnitedStates,anumberthatroseto241by1908.Inthatyear,HenryFordrevolutionizedthemanufactureofautomobileswithhisassembly-linestyleofproductionandbroughtouttheModelT,acarthatwasinexpensive,versatile,andeasytomaintain.TheintroductionoftheModelTtransformedtheautomobilefromaplaythingoftherichtoanitemthatevenpeopleofmodestincomecouldafford;bythelate1920sthecarwascommonplaceinmodernindustrialnations.

Automobilemanufacturersinthe1930sand1940srefinedandimprovedontheprinciplesofFordandotherpioneers.Carsweregenerallylarge,andmanywerestillextremelyexpensiveandluxurious;manyofthemostcollectiblecarsdatefromthistime.

TheincreasedaffluenceoftheUnitedStatesafterWorldWarⅡledtothedevelopmentoflarge,whilemostcompaniesinEuropemadesmaller,morefuel-efficientcars.Sincethemid-1970s,therisingcostoffuelhasincreasedthedemandforthesesmallercars,manyofwhichhavebeenproducedinJapanaswellasinEuropeandtheUnitedStates.TechnicalWords

windmill

n.；vt.；vi. 風車；使旋轉(zhuǎn)；作風車般 旋轉(zhuǎn)

mechanism

n. 機械裝置；機構(gòu),機制

interaction

n. 交互作用，交流

propel vt. 進,驅(qū)使

practice n. 實行,實踐

experimentaladj. 實驗的,根據(jù)實驗的norm n. 標準,規(guī)范freight n.；vt. 貨物，貨運；裝貨,使充 滿,運送petrol n. <英>汽油possessed adj. 著魔的,瘋狂的amazing adj. 令人驚異的maintain vt. 維持,維修r(nóng)efine vt. 精制,精煉collectible adj. 可收集的,可代收的PhrasesandExpressionsdifferentialmechanism 差速器

sparkingplug 火花塞NotesontheText1．LaterLeonardodaVincidesignedclockwork-driventricyclewithtillersteeringandadifferentialmechanismbetweentherearwheels.NotesontheText1．LaterLeonardodaVincidesignedclockwork-driventricyclewithtillersteeringandadifferentialmechanismbetweentherearwheels.后來，雷奧納多·達芬奇(LeonardodaVinci)設(shè)計了時鐘機構(gòu)驅(qū)動的機器三輪車，帶有舵柄轉(zhuǎn)向裝置和后輪之間的差速器。

2．Daimler’sengineprovedtobeagreatsuccessbecauseofitslessweightthatcoulddeliver1,000rpmandneededonlyverysmallandlightvehiclestocarrythem.戴姆勒的發(fā)動機被證實是一項偉大的成就，因為它的重量更輕，能輸出1?000轉(zhuǎn)每分鐘的轉(zhuǎn)速，只需非常小而輕的車輛來承載它們。

3．HebuiltthefirstV-Twinenginewithaglowingplatinumtubetoexplodethecylindergas－theveryearliestformofsparkingplug.他造出了第一臺V型雙列發(fā)動機，裝有用以使氣缸氣體爆發(fā)的白金管——早期的火花塞型式。

4．Formanyyearsaftertheintroductionofautomobiles,threekindsofpowersourceswereincommonuse:steamengines,gasolineorpetrolengines,andelectricmotors.在汽車進入人們生活之后很多年，三種動力源被普遍應用：蒸汽發(fā)動機、汽油發(fā)動機以及電動發(fā)動機。

5．Sincethemid-1970s,therisingcostoffuelhasincreasedthedemandforthesesmallercars,manyofwhichhavebeenproducedinJapanaswellasinEuropeandtheUnitedStates.自20世紀70年代中期始，燃油價格的上漲增加了這些小型汽車的需求量，許多日本生產(chǎn)的汽車也開始出現(xiàn)在歐洲和美國市場上。Exercises

Ⅰ.AnswerthefollowingquestionsinEnglish.

1．Whendidthehistoryoftheautomobileactuallybegin?

2．Whoisconsideredtohavebuiltthefirsttrueautomobilein1769?

3．Whytheearlysteam-poweredvehicleswereonlypracticalonaperfectlyflatsurfaceasstrongasiron?

4．WhobuiltthefirstV-Twinenginewithaglowingplatinumtubetoexplodethecylindergas-theveryearliestformofsparkingplug?

5．Whyhasthedemandforthesesmallercarsincreasedsincethemid-1970s?

Ⅱ.TranslatefollowingexpressionsintoEnglish.

1．差速器

2．火花塞

3．自動驅(qū)動汽車

4．V型雙列發(fā)動機

5．汽油發(fā)動機

6．現(xiàn)代工業(yè)國家

Ⅲ.TranslatefollowingsentencesintoEnglish.

1．17世紀初，小型蒸汽動力發(fā)動機出現(xiàn)了。

2．1885年卡爾·奔馳發(fā)明了汽油發(fā)動機。

3．戴姆勒為汽車的活力而著魔，想要為他的發(fā)動機注入新的特色。

4．汽車是便宜的，多功能的，易于維修的。

5．20世紀20年代，汽車在現(xiàn)代工業(yè)國家成為平常事物。

6．二戰(zhàn)之后美國的新富使發(fā)展更為迅速。

Ⅳ.Studythefollowinglistandname.*

1．two-doorsedan,four-doorsedan,fixedheadcoupe,hard-topsedan,limousine,stationwagon,dropheadcoupe,convertible,sportscar,minicar,jeep,fieldvehicle

2．bus,omnibus,servicevehicle,coach,luxurycoach,touringbus,articulatedbus,double-deckbus,passenger-trailer,minibus,microbus,articulatedtrolleybus

3．lorry,truck,high-wayvehicle,boardtruck,canvastop,box-vantruck,van,electromabil,deliveryvan,pick-up,cargo-bus,general-purposetruck,multipurposevehicleshort-wheelbasetruck

4．reardump,sidetipper,containercarrier,tank-truck,bulktruck,thermosvan,refrigeratedvehicle,furniturevanReadingMaterialRudolfDiesel—FatheroftheDieselEngine

Engineershavealwaysbeenconcernedwithefficiency,asinhowmuchcanbegottenoutofsomethinginexchangeforwhatisputintoit.Releasingstoredenergyismoredifficultthanusingenergythatisreadilyavailable:aboatcantraveldownstreamwiththecurrent(availableenergy);buttoreleasethestoredenergyinapieceofcoalrequiresthatheatbeappliedtoit.

Nomachineis100%efficient.Energyislostthroughfriction,airresistance,andheat.Anenginethatconvertshalfofitsfuelenergytousefulworkwouldbeconsidered50%efficient.Yetthemostsophisticatedsteamengineseverbuiltneverexceeded15%efficiency.

Isitanywonderthenthatbytheendofthe19thcenturyayoungengineerbythenameofRudolfDieselmadeithislifeambitiontoinventamoreefficientengine?

DieselwasborninParis,FranceonMarch18,1858,toBavarianemigrants.Hisfather,astrictdisciplinarian,wasaleatherworkerwhoforbidyoungRudolfandhissiblingsfromdistractinghisemployees,andsoRudolfspentmuchtimealone,honinghisartistictalentsanddistinguishinghimselfwithhisacademics.

In1870,theDieselfamilywasforcedtofleeFranceforthesafetyofEngland,theresultoftheFrench-Prussianwar.RudolfresumedhisstudiesinLondonwherehebecamefascinatedbythescienceandengineeringexhibitsatSouthKensington.

Rudolf’sfatherhadacousin,amathematicsprofessoratAugsburg’sRoyalDistrictTradeSchool,whotookRudolfinandsenthimtoschoolinAugsburg.Rudolfbecamesomewhatofachildprodigyandbyhisfourteenthbirthdayhaddecidedtobecomeanengineer.Asastudentengineer,Rudolfbecameinterestedintheconceptofwasteandwastemotion.Whenoneofhisprofessorssuggestedthatthebeststeamenginesweremerely6to10%efficient,Rudolfnotedinhisnotebook:“Studythepossibilityofpracticaldevelopmentoftheisotherm”.

Thesteamenginehadcausedarevolutionintravel.Firstintroducedin1804,bythetimeRudolfwasbornin1858,mostofEuropewasonrailways.Peoplefoundtheycouldnotonlytravelfromcitytocitymorequicklythaneverbefore,butthattheycouldalsoliveinoneplaceandworkinanother.Neverinhistoryhadtransportationchangedsodrasticallyinsobriefatime.Steampoweredrailwaysalsomadetransportofgoodscost-competitivewithwatertransport,andsomarineshippersbeganfittingsteamenginesinships.

Yetsteamenginescontinuedtobewastefulandfarfromfoolproof.Pipefailuresandboilerexplosionsfrequentlyoccurred,andsotheengineersofthattime,RudolfDieselamongthem,becamedriventofindasolution.

Inasteamengine,steammustfirstbeproducedinaboilerandthensenttoacylindertoperformitswork.Thenotionofgeneratingthepowerinthecylinder,therebyeliminatingtheboiler,hadoccurredtomanyinventors.ADutchscientisthadinventedthefirstinternalcombustionenginein1673;butsinceitfunctionedongunpowder,reloadingthegunpowderandbringingfreshairintothecylinderforthenextexplosionwasproblematic.Sincegaswouldbeunavailableuntilaround1,800,theinternalcombustionenginewasleftintheshadowsofthesteamengine.

Diesel’sessay,TheTheoryandConstr