In China's calendar, A, B, C, D, E, Ji, G, Xin, Ren and Gui are called "Ten Heavenly Stems", while Zi, Ugly, Yin, Mao, Chen, Si, Wu, Wei, Shen, You, Xu and Hai are called "Twelve Earthly Branches". The two cooperate with each other in a fixed order, forming the discipline of cadres and branches. In Ci Yuan, it is said that "dead branches" are meaningful to trees.
Extended data:
The invention of Ganzhi was named after the emperor's thirteen brothers. Besides Tian Ling, the emperor of the Central Committee, there are twelve brothers, namely Yu Feng, Xu Meng, Rouzhao, Yun Qiang, Zhu Yong, Tu Weiyue, Zhang Shang, Shi Guang, Xuannuo, Zhao Yang and Mao Yan.
On the other hand, the emperor took ten brothers as ten days' contribution, contributed twelve earthly branches to the mainland, and took ten (the name of the later Huangdi brothers) as twelve earthly branches, namely, struggle, red struggle, taking photos, single shovel, holding Xu, wild falling, resting, gas exploration and left peace.
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