Usingtoomuchwateror throwing rubbishintoourriversarecle...
問題詳情：Usingtoomuchwateror throwing rubbishintoourriversareclearwaysthathumanscanputourwatersupplyindanger，butwealsoaffectourwatersupplyinlessobviousways.Youmaywonderhowpaving(鋪砌)aroadcanleadtoles...