Is that you? Which John Smith extra 额外的overseas engineering company line Itaht you, John? Yes,speaking. (messsage)Tell Mary we'll be late for dinner this evening. I'm afraid I don't under stand Hasn't Mary told you? She invited Charlotte and me to dinner this evening. I said I would be at your house at six o'clock, I don't know when I'll finish. Oh, and by the way ,my wife wants to know if Mary needs any help. I don't know what you're talking about. That is John Smith, isn't it? You are John Smith, the engineer, aren't you? You work for the Overseas Engineering.He wants to know if why what when Yes under