第一,what引導(dǎo)的是賓語(yǔ)從句,你可以換為 the things that 引導(dǎo)的定語(yǔ)從句
你可以更改為：
he never agree to do the things that her mother asks her to 【這個(gè)是定語(yǔ)從句,the things是主句的賓語(yǔ),也就是從句that的先行詞,】
第二,her mother asks her to 【do省略了,和前邊的do是重復(fù)的】
即：
she never agree to do what her mother asks her to do
從句中what 做的是賓語(yǔ)
【俊狼獵英】 歡迎追問(wèn)