参考答案：evening

解析：[听力原文] 1-4
W: Good evening.
M: Hello. Do you have any vacant rooms at your hotel
W: I believe there may be one. Did you make a reservation in advance
M: No, we didn’t.
W: Well, we just received word that one reservation has been cancelled, so you arrived at a good time.
M: I suppose so. By the way, how much is the room
W: It’s $30 with TV and an extra bedroom. We have a pool in back.
M: That’s good. We need extra room for our two beds.
W: If it is OK, let’s step into our office to register.
M: Do you want the payment in advance
W: That’s our policy. I’m sure you understand.
M: Of course. What’s the number of the unit
W: No.61, on the second floor, over on the right. Here’s the key.
M: Thank you. I’ll park the car over there first. Then I’ll come right over to register.
W: Certainly, sir.