Ralph was a happy bear. He lived in a beautiful forest. Every day, Ralph picked the fruit on the trees. Ralph had many friends in the forest. Sometimes they went to the river together. They caught a lot of fish. One day, some people came and cut down hundreds of trees. They built a factory in the forest. The factory gave out smoke and dirty water. The forest was not beautiful any more. Ralph went to the river. The water was too dirty. There were no more fish in the river. Ralph felt very sad. In the end, he left the forest.