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ten celestial stems (two types each of wood, fire, earth, metal, water); ten heavenly stems
十干は暦の基礎として用いられた。
The ten celestial stems were used as the basis of the calendar.
十干と十二支を組み合わせて干支を作る。
The ten stems and twelve branches combine to form the sexagenary cycle.
十干の名前をすべて言えますか。
Can you name all of the ten celestial stems?