Three titles. In the Zhou dynasty, it was divided into five classes, namely, male, Hou, Bo, Zi and Gong. They are all hereditary, and the fiefs are called countries, and they exercise sovereignty in the fiefs. The vassal state, Qing, doctor, scholar and other titles, Chu, Gui, silks and other titles. Both Qing and doctor have fiefs, and they can also exercise sovereignty over fiefs, only under the orders of governors. Mencius and Zhang Wan: "There are sons of heaven, men, Hou, Bo, sons and men, all of which are five grades. Gentleman, lady, doctor, staff sergeant, sergeant, corporal, there are six grades. The system of the son of heaven is thousands of miles away. Public officials are hundreds of miles, men are 70 miles, and men are 50 miles, so they are all fourth-class. Can't be fifty miles, less than the emperor, attached to the princes. The emperor's son, doctor, and scholar, son and man. "

During the Warring States period, the vassal states generally abolished the feudal system of Doctor Qing, and implemented the county system, resulting in the emergence of titles such as Tong Hou and Jun, which were different from those of the former Doctor Qing. These new titles all had food cities of different sizes, but they could not be inherited.