In old time, local officials must offer some tributes to the Emperor each year. Mian Bogao, from Yunnan, was assigned to send a swan to the Emperor.
There was no transportation at that time and he had to walk to Chang’an. It was a long and hard time. He kept on walking without break whether day or night. A few days later, Mian Bogao was exhausted and also found the swan was very dusty. So he decided to help the swan take a bath in the river. As soon as the swan was put into the river, it fluttered its wings and flew away. Finally, Mian Bogao only got several feathers. He had no choice but to send these pieces of feathers to the Emperor. But surprisingly, the Emperor rewarded Mian Bogao instead of being angry！
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