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    Do you know pigeons? They are a kind of birds. They are in white and grey. Some people say they are not beautiful but they are cute and smart. Many people keep them as pets. Why do people say pigeons are clever? Because pigeons can take letters from one place to another. And they know the way home. We often see the picture of a pigeons with an olive branch(橄榄枝) in its mouth. We call them peace pigeons. They are the symbol of peace.