Xushen interpreted the Ten Heavenly Stems and the Twelve Earthly Branches as a system of the cycle of the seasons in "Shuowenjiezi".

《说文》中，许慎把“天干”、“地支”都解释为万物在一年中的萌发—生长—成熟—衰亡的循环系统。

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Heavenly Stems, Earthly Branches and the Twelve Animal signs(shengxiaos)are brainchild of Chinese ancestors. Generally, the former are used in calculating hours while the latter numbering years.

天干地支与十二生肖，是中国古代历法研究的成果，一般来说，十二生肖用于记年，天干地支计时。

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