- 問題詳情: Theworlditselfisbecomingmuchsmallerbyusingmoderntrafficandmoderncommunicationmeans.Lifetodayismucheasierthanitwashundredsofyearsago,butithasbroughtnewproblems.Oneofthebiggestproblemsispollution.Topollutemeanstomakethingsdirty.Pollutionc...
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