There used to be sixteen doors in Beijing, nine inside and seven outside. The nine inner doors are Dongzhi, Chaoyang, Chongwen, Zhengyang, Xuanwu, Fucheng, Xizhi, Desheng and Anding.

The outer seven doors are East, Refraction, Zuo 'an, Yongding, You 'an, Guang 'an and Bian Xi. When Zhu Yuanzhang came in and out, he inadvertently looked up and saw the plaque. The more he watched it, the angrier he became. He thinks that the "fishhook" can catch anything in the water except fishing, including dragons. The emperor is a dragon. Isn't that what he can catch? So he felt very angry and unhappy, so when he returned to the palace, he announced that no hooks were allowed on all the plaques in the palace.

The writing of the word "door" with no hook at the end originated in the Song Dynasty. After the Southern Song Dynasty moved its capital to Lin 'an, the Jade Emperor Hall caught fire and all the doors were burned down. Some ministers said that the door characters in the plaque of the Palace Que had a hook and a fire pen in the last stroke, so a fire broke out. In order to avoid the fire, all these plaques were burned. From now on, no plaque with the word "door" in the palace can be ticked.

However, the significance of the door lies not in the way a word is written, but in the role it plays in our lives. Everything in the world, including people, can only progress and develop through communication, and the door has become an important channel for people to communicate with the outside world.

The Qing dynasty closed its doors to the outside world, and this door only kept the feudal and decadent rule in order to stop the progressive civilization; From the founding of New China to the reform and opening up, this door has come back to life. We go to the world from here, and the world enters China from here.