A: I'm sorry, but this is my seat.
B: Really? What is your seat number?
A: 12A. It is in this row and beside the window.
B: Are you traveling alone?
A: Yes, what's wrong?
B: Would you mind changing the seat with me?
A: Why?
B: I'd like to sit with my friends.
A: Urn, let me think about it.
B: I'll feel sick if I don't sit at the window seat.
A: That's all right. Where is your seat?
B: It's 13C. And let me help you with the luggage.
A: Thanks a lot.
B: It is I who should thank you.