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We are living a happy life. Our parents love us so much that we can have what we want. But some of our classmates do not take good care of these things. They throw away their pens and paper. Some of them even waste food. I think it is a bad habit. We should protect environment of the school and the city. We shouldn't step onto the grass, and we shouldn't pick the flowers. Try to go to school by bike or on foot. Don't use plastic bags. Every year we can plant many trees, the environment will be better and better.