who is that speaking?为什么回答是This is...speaking

who is that speaking?为什么回答是This is...speaking hello who is that speaking什么意思 Who is that speaking 回答用this 还是that ━━This is Thomas speaking 的 问句是什么?1who speakings? 2who is that speaking? 3what are you speaking? 4who's going to speaking? 对This is Tom speaking.中的Tom怎么提问?是Who is that?还是Who is that speaking? who's that speaking选A .This is Tom.还是B.That's Tom speaking That is the man to______(who)we were speaking. who is the women that is speaking at the meeting 中that为什么不能换成who who is the women that is speaking at the meeting 中that为什么不能换成who 1、- Who's that speaking?- This is Tom______.A：speaks B：spoken C：speaking D Is that Miss Li speaking?yes,this is Mis Li speaking ____________?A who are you Bwho is he C who is she D who is that Hello!Is that Mr Wang speaking?--Yes,____________?(AI' m speaking 对么B who' s that Cwho' s that 怎么回答is that tom speaking?is that tom speaking?yes.__________应该添who'that 还是 speaking.参考书的答案是第一个 ---hello,is this Mr.liu speaking?----(yes,who is that?that怎么理解 If you want to know who is answering the telephone call,you should say：A.Who is speaking over tA.Who is speaking over there B.Who are you speaking C.Who is that,please? This is John speaking.Who's that?A.I;m Bill.B.This is Bill.C.That's Bill speaking.D.I'm Bill speaking. 1、- Who's that speaking?- This is Tom__C___.A：speaks B：spoken C：speaking D：saying 2、- Is Ma Who is the boy ____ is speaking there?Who is the boy____ is speaking there?A.whom B.that C.which D.who这是一个定语从句吧,答案填that,但为什么不能填who?who不是能指人吗?