What is speaking?/ What is it speaking?

What is speaking?/ What is it speaking? Generally speaking,being hard-working is just what it takes What should student do when someone is speaking? what is the purpose of speaking well 怎么翻译 generally speaking ,what is the end of marriage without love Is that Mary speaking?Yes ,it is hello it is jack speaking?yes （ ） This is Helen speaking. this is tom speaking ---------------------is that speaking Who is that speaking? ( this is Kangkang speaking.