In 1850,two thirds of the land was coverd by trees,and they made the world look very brautiful.But later,the human being started chopping down the trees.Many forests disappeared,and there was nothing left on the ground.Now,people realized that it is wrong to chop up the trees,so they are beginning to plant trees and to build the new forests.
上面几位一定是用什么翻译软件翻的吧.一点也看不懂.