Each person need to pay more attention on environment.Currently ,many trees were cutted down .More and more sand was brought into our life .What is worst ,it caused dust-storm and made our living environment became worse and worse .To some extent ,it will cost a loss to us .We must build the great gree wall in hurry .Hope this can prevent enviroment from getting worst .For our lives ,it is important for us to protect our living enviroment .