He extended it and developed it into a theory of psychosexual development.

他扩展了它并将其发展成为性心理发展的理论。

It can have a serious effect on your psychosexual development.

会给你们性心理发展带来不好的影响。

The question is: The conflicts in psychosexual development that Freud describes is--always assumes that a child has a mother and a father, one of each, in a certain sort of familial structure.

问题是：弗洛伊德所描述的性心理发展中的冲突是——总是假设孩子在某种家庭结构中有母亲和父亲，每人各有一个。