Good morning, everyone!

    We are all living in this city. It's our duty to keep it clean and tidy. We shouldn't spit in public places, such as

in the street, park or on the square. We shouldn't throw rubbish here and there, either. Besides, we must protect trees and flowers. And we must take some steps to stop people from polluting the river. If everybody tries his

best to do something useful for our city, our city will become more beautiful.

     That's all. Thank you.

答案不唯一