Hey, you know who else who stays late is, um, Stacey.

你知道还有谁也加班吗 史黛丝。

That is, can distinguish between them, do you know who is who?

意思就是，能够分清两者，你知道谁是谁吗？

Toxic relationships can be very confusing at times, making it difficult to know who is who in the zoo.

有害的关系有时会让人很混乱，让人很难分清到底谁是何种定位。

Tonight, no one knows who is who, and reality seems a distant dream.

今夜， 无人知晓谁是谁非，现实仿佛是一场遥不可及的梦。