人教版-英语-必修五-课文-电子版.docx

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1、Unit1GREATSCIENTISTSJOHNSNOWDEFEATS“KINGCHOLERA”JohnSnowwasafamousdoctorinLondon—soexpert,indeed,thatheattendedQueenVictoriaasherpersonalphysician.Buthebecameinspiredwhenhethoughtabouthelpingordinarypeopleexposedtocholera.Thiswasthedeadlydiseaseofitsday.Neitheritscausenoritscurewasunderstood.S

2、omanythousandsofterrifiedpeoplediedeverytimetherewasanoutbreak.JohnSnowwantedtofacethechallengeandsolvethisproblem.Heknewthatcholerawouldneverbecontrolleduntilitscausewasfound.Hebecameinterestedintwotheoriesthatpossiblyexplainedhowcholerakilledpeople.Thefirstsuggestedthatcholeramultipliedinthe

3、air,acloudofdangerousgasfloatedarounduntilitfounditsvictims.Fromthestomachthediseasequicklyattackedthebodyandsoontheaffectedpersondied.JohnSnowsuspectedthatthesecondtheorywascorrectbutheneededevidence.SowhenanotheroutbreakhitLondonin1854,hewasreadytobeginhisenquiry.Asthediseasespreadquicklythr

4、oughpoorneighbourhoods,hebegantogatherinformation.Intwoparticularstreets,thecholeraoutbreakwassoseverethatmorethan500peoplediedintendays.Hewasdeterminedtofindoutwhy.Firsthemarkedonamaptheexactplaceswhereallthedeadpeoplehavelived.Thisgavehimavaluableclueaboutthecauseofthedisease.Manyofthedeaths

5、werenearthewaterpumpinBroadStreet(especiallynumbers163738and40).Healsonoticedthatsomehouses(suchas20and21BroadStreetand8and9CambridgeStreet)hadhadnodeaths.Hehadnotforeseenthis,sohemadefurtherinvestigations.Hediscoveredthatthesepeopleworkedinthepubat7CambridgeStreet.Theyhadbeengivenfreebeerands

6、ohadnotdrunkthewaterfromthepump.Itseemedthatthewaterwastoblame,Next,JohnSnowlookedintothesourceofthewaterforthesetwostreets.HefoundthatitcamefromtheriverpollutedbythedirtywaterfromLondon.HeimmediatelytoldtheastonishedpeopleinBroadStreettoremovethehandlefromthepumpsothatitcouldnotbeused.Soonaft

7、erwardsthediseasesloweddown.Hehadshownthatcholerawasspreadbygermsandnotinacloudofgas.InanotherpartofLondon,hefoundsupportingevidencefromtwootherdeathsthatwerelinkedtotheBroadStreetoutbreak.Awoman,whohadmovedawayfromBroadStreet,likedthew