三合

三合, the trine, is three branches gathering to form a single breath.

申子辰 make water, 亥卯未 wood, 寅午戌 fire, 巳酉丑 metal.

All three present is a full trine; two, including the 旺 branch, is a half trine.

Where a trine stands, the reckoning of the five breaths changes.