Introduction to "Liu Yu Plaque": "When entering Kangwanwan, first look at the Liu Yu Plaque." "Liu Yu" is the symbol of Kang family manor culture and the treasure of the town hall. This unique plaque hanging directly above the entrance hall is the Kang family's family motto "Leave You". The two prominent seal characters in front are the two characters "Liuyu" with room for it. The content above it is mentioned at the beginning: "Taoist Liugeng's "Four Liu Inscriptions" says: Leave more than you can, and you can use your endless ingenuity to repay good fortune; If there is something left over, the endless wealth can be returned to the people; if there is something left over, the endless blessing can be returned to the descendants." Here are four mottos from Wang Boda, a Taoist who left farming in the Southern Song Dynasty, as a warning. Children and grandchildren should leave room for everything. In life, do not use up all your blessings, wealth, longevity and wealth, but leave them to those who need them. Then, he quoted two sentences from Gao Jingyi, a Jinshi of the Ming Dynasty: "If you take one step when it comes to matters, you will have room for yourself; if you relax a little when it comes to wealth, you will have your own aftertaste." It can be said that the idea of leaving room for others has been brought to its extreme. Finally, he concluded: "Do you know the way of the Chang family? It's just to leave something behind and avoid using it up." The way of the Chang family is to leave something behind and avoid using it up. This sentence shows that the secret of the Kang family's prosperity for four hundred years is everything. Leave some room, be careful not to overfill or overfill. That is to say, "Endure the calm for a while, and take a step back to open up the sea and the sky." This plaque is now listed as one of the famous Chinese plaques.