As time goes by, man is making the earth sick. peopie cut down too many trees and leave rubbish everywhere. factories let out their wastes without doing anything with it, this has caused some serious problem.such as,the gas is smell serious ,the river is dirty,.what shall we do to save the earth? My suggestion is that we should plant more trees,put the rubbish into dustbins and stop factories pouring wastes directly into the air or river. In all,we have only one erath,so we should do everthing to protect it. or we will regret.