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JuanLouis,ajuniorgeologymajor,decidedtogiveaninformativespeechabouthowearthquakesoccur.Fromhisaudienceandanalysishelearnedthatonly2or3ofhisclassmatesknewmuchofanythingaboutgeology.Juanrealizedthenthathemustpresenthisspeechatanelementarylevelandwithaminimumofscientificlanguage.Ashepreparedthespeech,Juankeptaskinghimself,“HowcanImakethisclearandmeaningfultosomeonewhoknowsnothingaboutearthquakesorgeologicalprinciples?”SincehewasspeakingintheMidwest,hedecidedtobeginbynotingthatthemostsevereearthquakeinAmericanhistorytookplacenotinCaliforniaorAlaskabutatNewMadrid,Missouriin1811.Ifsuchanearthquakehappenedtoday,itwouldbefeltfromtheRockyMountainstotheAtlanticOceanandwouldflattenmostofthecitiesintheMississippivalley.That,hefigured,shouldgethisclassmates’attention.Throughoutthebodyofthespeech,Juandealtonlywiththebasicmechanicsoftheearthquakes,carefullyavoidtechnicalterms.Healsopreparedvisualaids,diagrammingphotoline,sohisclassmateswouldn’tgetconfused.Tobeabsolutelysafe,Juanaskedhisroommate,whowasnotageologymajor,tolistentothespeech.“Stopme,”hesaid,“anytimeIsaysomethingyoudon’tunderstand.”Juan’sroommatestoppedhimfourtimes.Andateachspot,Juanworkedoutawaytomakehispointmoreclearly.Finally,hehadaspeechthatwasinterestingandperfectlyunderstandabletohisaudience.

注：机器翻译不要,谢谢了.