I don't know the _____between them .

i don't know all of them I don't know any of them don't know what is the difference between them”和“I don't kno I don't know them.为什么接宾格them I don't know I should keep them. there are too many people in the hall .i don't know __ them Both the two girls are new to me.I don't know ____ of them But I don't know where t______ find them you can ask them与 I don 't know I don't know the......the question i don't know when the manager I don't know the teacher----- is