Que vs Qui

Question

I thought I understood when to use que vs qui until I encountered this question in B2:La femme________ je travaille est très sympa. (The woman for whom I work is very nice.)'pour qui' or 'pour que'
It seemed to me the subj.present verb 'travaille' had the ''subject je so the qui/que was providing the object, hence I chose que, but apparently the answer is qui. See also tips in the above lesson, since it is followed by je shouldn't it be que?

Answer

"Qui" can work as an object when it is preceded by a preposition like "pour" or "à". In English, it would mean "whom" although everyone says "who" which has become accepted. Example: "C'est la femme à qui je parlais." "That's the woman to whom I was speaking."

Answer

I have found that if you can use 'that' in the sentence you need que, and if you can't use 'qui'