Question

who is she和 who is that有什么区别，如何回答

Answer 1

---Who is she? (在视力范围内，或图片中的人物询问）她是谁？
---She is my mother/ my teacher of English/ Mary's mother/ our boss.
---Who is that? 电话用语：哪位（打来的电话）？
---(This is) Mary speaking.= (It's) Mary speaking. = (It's) Mary here. 是Mary.

Answer 2

who is that？这句话是用于门铃响了之后问的话，who is she？这句话用于谈话时询问她是谁

Answer 3

第一个是当你知道那个人是女性的时候用的。
第二个是你接电话时候用的。接电话时候，你并不知道对方是男是女。用who is that 问对方是谁！