Nowadays the problems about environment become more and more serious.There are so many pollutions and natural disasters in the world,and they all have the unpredictable effect.More and more factories function,follow that also have some water pollutions,air pollutions.As for the special air can make holes in the ozone layer,destroy the atmosphere as well.Flood,desert,dry,such the disasters like those probably will be happen in next time.Therefore in that time as hard as we can to save the earth is the most important thing to do.