1, the eight-character disagreement means that both parties belong to each other when they were born. Constellation, or date of birth, is a person's date of birth. Annual stems and branches form annual columns, monthly stems and branches form monthly columns, daily stems and branches form daily columns, and seasonal stems and branches form hourly columns; One * * * four pillars, four stems and four branches * * * eight characters, so it is also called four pillars and eight characters.

2. Astrology is an ancient marriage custom in China. After the marriage proposal of the matchmaker is approved by the woman's family, the two sides exchange Geng posts, which are called eight-character combinations according to the zodiac signs of the two sides' dates of birth.