According to ban zhao, what were women's roles and purposes? how did ban zhao's approach fit the definition of patriarchy?

In Ban Zhao, women had roles that only served their husbands. Women were to be completely subservient and live only to serve and benefit their husbands while expecting nothing for themselves. Under this, women had no protection at all - slavery is a more accurate term. Women could be abused, abandoned and even killed with the man not being help responsible for any wrongdoing. This fits the definition of Chinese patriarchy because it placed women in roles where men were 'above' and to be served no matter what while women were seen as less and had high expectations placed on them.