Lesson34Unit9:Earth,AirandWater课件
日期:2010-07-02 07:25
AirandWaterLakeBaikalDunhuangGebiIndiaMediterraneanSeaGermanyUSAAlskaChinaRussiaEARTHAIRWATERManypartsoftheworldwithlargepopulationandplentyofcropshavebecomedesert2Landmaybecomepooriffarmersdonotlimittheircattle3Goodsoilisgraduallylostthesedaysastreesarebeingcutdown4Airpollutionandwaterpollutionarethetwocausesofproblemthatmanypartsoftheworldhavebecomedesert5Chemicalsinthesmokefrompowerstationscantravelhundredsofmilesbeforefallingdowntotherain6Afterabadaccidentatanuclearpowerstation,50%ofthetreesinGermanyweredamaged7ThewriterusestheexamplesoftheaccidentsinbothIndiaandRussiatoexplainhowwaterispolluted8Onceoceansarepolluted,SavingtheearthLesson34Unit9Earth,theyarenotabletocleanthemselvesManypartsoftheworldwithlargepopulationandplentyofcropshavebecomedesert(T)2Landmaybecomepooriffarmersdonotlimittheircattle(T)3Goodsoilisgraduallylostthesedaysastreesarebeingcutdown(T)4Airpollutionandwaterpollutionarethetwocausesofproblemthatmanypartsof,
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