In the early Tang dynasty, the army followed the "officer system". On the basis of farmers with farmland system, there are 634 military offices in all provinces, prefectures and counties in the world, which are collectively called passbook houses. According to the size of the preparation, it is divided into upper, middle and lower levels. The Chief Administrative Officer is a surname (fourth grade), and the Deputy Chief Administrative Officer is Guo Yi. The regiment consists of a regiment (also known as a battalion), an officer, a captain and a team. Five teams in each battalion, three teams in each team, five captains in each team and ten captains in each team. Battalion is the basic unit. According to the functions and equipment of the service, it can also be divided into base, chariot riding, shooting, leaping riding, stepping and long water. The official ranks of its subordinate officials are: don't drive, long history, six Cao Wei, and join the army. In charge of the garrison and military households in various places, the government is divided into upper, middle and lower levels according to the scale, and takes turns to perform military service five times a year, about 1000-4000 people. At its peak, there were more than 600 governments in China, which counted more than 700,000 soldiers. Keep one-third in service all the year round. Sixteen generals' yamen were set up in the central government to take charge of the world's military horses, that is, left and right guards, left and right guards, left and right guards, left and right guards, and left and right guards. In addition to the left and right guards and the left and right guards, the guards also led more than 300 government soldiers in the customs. There are basically no generals at the highest level, with the generals in charge of the Guards and the officers of the 16th Guards as the given generals, as well as corps commanders, corps commanders, left and right corps commanders, and clerks, Cang Cao, Bing Cao, Cao Qi and Cao Zhou joining the army. Each guard maintains 25,000-40,000 guards, led by a standing army. The establishment of the grass-roots battalion of the guards is slightly higher than that of the government soldiers, and it is customarily called Wei. Battalion-level officers are mostly brigade commanders, and the chief is Angelababy Lang Jiang, whose rank is higher than that of government soldier Guo Yi. There are about two or three hundred thousand standing army horses.