提示：Mary与Bill不期而遇，邀请他一起吃晚饭。但Bill当晚7点要去北京，下周一回来。 Mary让Bill回来后给她打电话。（Mary=M；Bill =B） M：Bill，is that you？I haven't seen you for a long time. B：Hi，Mary.Great to see you again 51 ？ M：Fine.Why don't we get together and have a chat？How about 52 this evening？ B：Well，it sounds great，but I'm 53 at 7 o'clock. M：What a pity！ B：Well，I'Il be back 54 . We can find a time to meet again. M：Okay. 55 when you are back.
B：No problem.Coodbve！ M：Bye！
1. 根据中文提示，把 51 缺少的内容写在线上。
补全对话∶共5句。根据中文提示，把对话中缺少的内容写在线上。这些句子必须符合英语表达习惯。打句号的地方，用陈述句;打问号的地方，用疑问句。
提示：Henry准备去上海开会，打电话到航空公司订票，工作人员Lillian接听了电话。
(L = Lillian; H = Henry)
L：Hello! This is Air China.________51________?
H：Hello. I’d like to book a flight from Beijing to Shanghai.
L：Sure. ________52________?
H：This Saturday morning July 12.
L：OK. How many tickets?
H：________53________.
L：So, that’s one ticket from Beijing to Shanghai.
H：________54________?
L：Well, that will be 1,030 yuan.
H：OK. Can I book that now?
L：Certainly.
H：________55________.
L：You’re welcome.
2. 请根据中文提示，回答________53________对话中缺少的内容。
3. 请根据中文提示，回答________51________对话中缺少的内容。
提示：Tom给Jack打电话，但Jack不在办公室，便请Mary留言给Jack。
（T=Tom；M=Mary）
T:Hello！This is Tom. Who’s speaking there？
M:Hello,（51）.
T:Hi，Mary！Can I talk to Jack，please？
M:I'm sorry.（52）.
T:Well，can you take a message for him？
M:（53）.
T:Please ask him to call me back. We are going to visit our teacher this evening.
M:I see.（54）？
T:My phone number is 54211188.
M:OK，I'll tell him when he comes back.
T:（55）.
M:You are welcome.
