Unit15WelcometoSanFrancisco预习导学学习本单元所掌握的重点知识单词（四会要求）Trolleybus,normally,quick,line,bridge,rather,public,narrow,advantage,advise,market,debate,engine,speed,bay,streetcar,connect,district,railway,trip,wise,include短语：1.advisesb.nottodosth.2.enjoyourgoodpublictransit3.old-timetrolleys4.travelupanddownMarket5.thecenterofmanyofdebates6.thebuttofmanyjokes.7.dependon8.thespeedofthecable9.9.5milesanhour10.nevermore,neverless11.offerawideviewofthecityandbay12.suchas13.makeanothersuggestion.Dressinginlayers14.awisedecision15.15.15.makeup16.16.16.manydifferentkindsofweather句型：WouldyouliketocometoSanFranciscoforavisit?NovisittoSanFranciscoiscompletewithouttakingarideonacablecar阅读文章总结一下说明文的写作方法
