San He
Shen-Zi-Chen, Hai-Mao-Wei, Yin-Wu-Xu, Si-You-Chou — each group of three Earthly Branches combines to form a Five Element phase. On the Chinese almanac, 'San He' indicates the day's Earthly Branch and the month's branch form such a combination, traditionally considered auspicious for alliances, marriages, and business openings.
Shen-Zi-Chen combine into Water, Hai-Mao-Wei into Wood, Yin-Wu-Xu into Fire, Si-You-Chou into Metal — three Earthly Branches combine to form a Five Element phase.
Each trio consists of the stages of Longevity (Chang Sheng), Emperor's Peak (Di Wang), and Tomb/Storage (Mu Ku) for that element, so 'San He' signifies the complete cycle 'from birth to peak to containment,' representing the fullest power.
On the Chinese almanac, 'San He' indicates the day's Earthly Branch and the month's branch form such a combination, traditionally considered auspicious for alliances, marriages, and business openings.