根据对话内容填空（每空1分，共5分）
(Kangkang is booking train tickets to Mount Tai.)
Clerk:    Hello, Beijing Railway Station. Can I help you?
Kangkang: Yes, I’d like to book some tickets to Mount Tai     March 13^th.
Clerk:    OK. The train leaves at 11:45 a.m. and     at Taishan Railway
Station at 6:44 p.m.
Kangkang: Great. And what about the    ?
Clerk:    We have tickets at ￥145 for the hard sleeper and ￥224 for the soft sleeper. What _   do you want?
Kangkang: I’d like to book 21 hard sleeper tickets.
Clerk::    Please     for the tickets before 5:30 p.m. May I have your name and telephone number, please?
Kangkang: Sure. I’m Li Weikang and my telephone number is 8250-2448. Thank you.
Clerk:    You’re welcome.