补全对话（5小题，每小题2分，共10分）
根据下面的对话情景，在每个空白处填上一个适当的句子，使对话的意思连贯、完整。
A: Hi, Mei.　　　　　　　　.
B: Yes. I have just heard that I had got the chance to go to Switzerland on my student exchange program.
A: Really? How lucky you are!
B:　　　　　　　　. You know I have to live with my host family. I have never been there before, so I don’t really know what I am supposed to do.
A:　　　　　　　　. I know something about that. First, don’t be late. In Switzerland, it’s very important to be on time.
B:　　　　　. I think I’ll have to buy a watch.
A: And you can’t visit other people’s homes without calling them first. If you want to visit your friends, you must call them first.
B: Oh, that’s pretty different from the customs in Colombia where I am from.　　　　　　　　.
A: Yes, that’s the difference. Good luck!
B: Thank you!