Man: Can I use the conference room tomorrow?
Woman: Sure, as long as it is not booked.
Man: What should I do if it is?
Woman: If it's booked, you can use the lecture hall.
Man: Oh, that is too big I think.
Woman: Well, the conference room might be free. I'll check and let you know if it is. If it isn't, what should I do?
Man: If it's booked, then I will wait until it is free. The lecture hall is too big.
Woman: OK, I'll get back to you soon.
Man: Great. Thanks.