It is said that it was created by Zhao, the queen of Emperor Han Chengdi. Zhao Yanfei is a famous master and queen of Emperor Han Chengdi, who is good at singing and dancing. Because of its thin figure, it is said that it can "dance on the palm of your hand", so it is called "flying swallow". She is light and soft, and can't stand a gust of wind when dancing. The emperor's old son made a crystal plate for her to dance, and specially made a seven treasures shelter platform for fear that she would be blown away by the wind-it is estimated that Ye Zhao is a folk martial artist with extremely light flying skills, not only "flying on the grass" but also "riding against the wind". The word "Yan", later called "Yan is thin and fat", is Zhao, which means a kind of thin and light beauty.