I used to live in a small town with trees all around. There was no tall building and the only street was narrow. Just outside the town， there was a river. You can see different kinds of fish swimming in the clear water. People here lived a simple life.

　　Great changes have taken place here. You can see tall buildings， big department stores and factories everywhere. Different kinds of cars and buses are running in the big streets. But with the development of the industry， we have fewer trees. Air and water pollution is becoming more and more serious. We must do something to stop pollution and make our town even more beautiful.