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2、Unit1PresentingaSpeechRoadBuildingGoodmorning,everyone.TodayI'llbetalkingabouttherelationshipbetweenroadbuildingandthedevelopmentoftheAmericaneconomyduringthe18thcentury.About300yearsago,theUnitedStates'economywasgrowingrapidly,mainlybecauseofaboomi
3、ngtradeintwoimportantagriculturalproducts:grainandcotton.GrainoutputintheeasternpartofAmericaincreasedquicklyatthattimeduetotherapidlygrowingpopulationandthelargenumberofimmigrantsfromEurope.Asaresult,thedemandforgrainalmostdoubled.Forthisreason,thet
4、radeingrainfirstdevelopedinthispartofthecountry.Atthesametime,theroadsystemwasgraduallybuiltupinordertotransportthegrainfromtheruralareastovariouscities.Theroadbuildingclearlyhelpeddeveloptheeconomyquicklyintheseareasandinthecitiesaswell.Duringthesam
5、eperiod,farmersintheSouthcouldgetalargeamountoflaborersfromAfrica,andtheystartedtogrowcotton.Asthecottonoutputincreased,thefarmersneededtosellitinotherplaces.Asaresult,manyroadswerebuilttolinktheruralareastothecities.Atfirst,thistradeofgrainandcotton
6、tookplacealongthecoast,ornearriversandlakes.Ittookplacetherebecauseitwaseasyandcheaptotransportgoodsfromoneplacetoanother.Before1700,itwasveryexpensivetomovethegoodsbyroad.So,farmershadtorelymainlyonriverstomovetheircropstomarkets.Atthattime,therewas
7、onlyonecontinuousroadthatexistedintheUS.Itranfromnorthtosouthalongcountryroads,whichwerelinkedtogethertomakeonelongroad.Withinashorttime,thefirsteast-to-westroadswerebuilt.Theywerecalledturnpikes.Privatecompaniesbuilttheseroadsandcollectedfeesfromall
8、vehiclesthattraveledonthem.Eventually,becauseoftheboomingtradeofgrainandcotton,anetworkofroadwayswascompletedthatconnectedsomemajorcitiesandtowns.Althoughtravelingwasstillcostlyforfarmers,theysoonpreferredtomovetheircropstocitiesandotherareasonroadwa
9、ysratherthanbyboatbecauseitwasfasterandmoreconvenient.SoherewecanseearatherclearpictureofroadbuildingintheUnitedStatesanditsimpactoneconomicdevelopmentduringthatperiod.TheMississippiRiverinAmericaGoodafternoon.Todaywe’regoingtotalkabouttheMississippi
