Know three obedience (don't marry your father, marry your husband, and your husband dies from your son), be familiar with the four virtues (women's virtue, women's words, women's appearance, women's virtue), and understand (nine chastity, seven fierceness).

Nine chastity and seven fierceness is a general term, which is a kind of praise to women. Used of a woman who would rather die than remarry and never lose her virginity. !