What is the relationship (关系) between Mr. Rance and John?

M: Hello! Could I speak to Mr. Rance, please?
W: Oh, sorry, he’s out at the moment.
M: Is that Mrs. Ranee?
W: Yes, it is. Who is that?
M: This is John.
W: Hi, John. Can I take a message for you?
M: Yes, please. I’ve caught a bad cold. I’m afraid I can’t go to school today.
W: I’m sorry to hear that. You’d better go to see a doctor. And I’ll tell him as soon as he comes back.
M: Thanks a lot. Goodbye.
W: Goodbye.