![霧霾的危害英語作文：Air Pollutant]( "霧霾的危害英語作文：Air Pollutant")
- Thiskindofairpollutantcomefromavarietyofnaturalandmanmadesources.Naturalsourcescanincludewindblowndust,andsootfromwildfires.Manmadesourcescanincludemotorvehicles,andindustrialfuelburning,andmanufacturingoperations.Theoneofthemaincausethattouchesoffha...
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