Withtheexplosionofpopulationintheworld,moreandmorepoisonouswasteisproduced.Asaresult,alotofriversandlakesarepolluted.Insomeareas,theairalsobecomesdirtyandharmful.Consequently,animalsandplantsareendangered.Andpeople'shealthisgreatlyaffected. 　　Fortunately,moreandmorepeoplehaverealizedtheserioussituation.Manycountrieshavepassedlawstopreventtheenvironmentfrombeingfurtherpolluted.Peopleareworkinghardtofindwaystokeeptheearthclean:theytreatwastegases,protectwatersourcesandpurifywastewater.Definitely,controllingtheincreaseofpopulationisoneofthemostefficientways. 　　However,infuturemoreeffortswillbeneededtowinthebattleagainstpollution,Thelawscontrollingpollutionmustbestrictlyenforced,Andaboveall,attentionshouldbepaidtotheeducationofthepeoplesothateveryonewillshowhisconcernaboutenvironmentalprotection.