Ourearthisintrouble.Ourdrinkingwaterisbecomingdirtier,a...
問題詳情：Ourearthisintrouble.Ourdrinkingwaterisbecomingdirtier,andtheairisnotasclearasbefore. Rivers,lakesandseas__61____(pollute)bypeopleand__62__(factory).Youmightthinkthereisnothingyoucando__63____...