Unit4Behindbeliefs课外阅读阅读文章，选择正确答案，回答问题。Peopleandthesourcesofairpollutionarefoundinthesameplaces.Thismeansthatcitieswithlargepopulationshavethebiggestproblemofdirtyair.Airpollutioniscausedbymanydifferentthings.Amajorsourceofairpollutionisthegasfumesfromcars.Statisticsshowthat93percentofallautotripsarewithincities.Anothermajorsourceofdirtyareistheburningofcoalandoilforenergy.Thisenergyisneededtomakeelectricity.Ofcourse,muchmoreelectricityisusedinthecitythaninthecountry.Ontheaverage,wethrowawaymoretrashandgarbagethantheyearbefore.Theburningofgarbagecontributestoairpollution.Manymajorindustriesarealsoresponsibleforthedirtyairinthearoundcities.Thefumesfromiron,steel,chemical,andpetroleumproductionaddparticlestotheair.Theeffectsofairpollutionrangefrommildheadachestodeath.Thelevelsofpollutionfoundinheavyfortrafficmaycauseheadachesforlossofclearvision.Wherevercoalandoilareusedforfuel,fumesmaykilltreesandplantsandcausemetaltocorrode.Insomeofthelargercities,thesefumesendangerthelifeofhumanbeingsbycontributingtolungdiseasesandcausingearlydeath.1.Thekeypointofthepassageisthat______.A.thecauseofairpollutionispeopleB.thecausesandtheeffectsofairpollutionarebothfoundincitiesC.theeffectsofairpollutionrangefromheadachestodeathD.airpollutioniscausedbydirtyair2.Whatisthepurposeofthispassage?A.TopersuadepeopletostoppollutingtheairB.TotellthecausesofairpollutionC.TotellwhycitiesarebadplacestoliveD.Todescribewhycitiesarebadplacestolive3.Whyisairpollutionmoregraveinthecitythaninthecountry?A.Becausetherearelargerpopulationsincities.B.Becausetheairinthecityisdirty.C.Becausetherearemorecarsinthecity.D.Becausetherearemuchmoregasfumesfromcarsandburningofcoalandoilforenergyinthecitythaninthecountry.4.Thefumesfromcoalandoilmaycausemetal______.A.toturnblackB.tobecomerustyC.tocorrodeD.totwist5.Inlargercities,thefumesfromcoalandoilmaycontributeto______.A.heartdiseaseB.lungdiseaseC.lossofclearvisionD.seriousheadache答案：1.B2.A3.D4.C5.B
