Problem: W: Yes, of course. What was said before this conversation?

A: M: Excuse me, I bought this white shirt here yesterday. Can I change it for a larger one?
Problem: Given the question: W: I haven't got any plans yet, why? M: There is an exhibition of Chinese paintings at the public library. Would you like to go with me? W: I'd love to, but when? M: How about Saturday morning? It's cooler in the morning and maybe less crowded. W: I'm afraid I can not get up early on weekends. I'd prefer Saturday afternoon. Believe me there won't be too many people. M: So, shall we meet at 2:00, Saturday afternoon? W: OK, that would be great. I'll be waiting for you at my home. What was said before this conversation?
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The answer is:
M: Are you free on the weekend?
input question: W: Fine. Thanks. M: Tomorrow is my birthday. I would like to invite you and your family to my birthday party. Our teacher Mr. Wang in University will come also. W: Thank you very much. When will it begin? M: At 6:30 pm. W: Oh. Let me see. I get off work at 5:30 every day and then spend about 35 minutes on meeting my husband and my daughter, We shall cost about 45 minutes to go to your home. Is that all right? M: Yes, of course. W: OK. See you tomorrow. M: See you then. What was said before this conversation????
output answer: M: Hello. I haven't seen you for a long time. How are you?
M: Some of these books aren't so old, though... See? This mystery was published only six years ago. It cost seventy-five cents. You can't beat that. W: Hey! Look at this! M: What? Are you getting interested in nineteenth century poetry all of a sudden? W: No. Look at the inscription! Someone gave this book as a present, and wrote a note on the inside of the front cover. It's dated 1893. Maybe it's worth something. M: Everything on that shelf is worth fifty cents. W: But if this is a signature of someone who is well known, it might bring a lot more. I hear William Shakespeare's signature is worth about a million dollars. What was said before this conversation?
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Answer: W: I enjoy going through a secondhand bookstore, don't you? It's interesting to see what people used to enjoy reading. Did you see this old book of children's stories?
Q: W: Oh, David. I had an argument with mum again. I'm not getting enough pocket money. M: How much do you get? W: Five pounds a week. M: That sounds reasonable to me. W: Well, I'm 14 and if you are going to town shopping, you can never have enough money. Everything is so expensive. M: But is it fair amount of money? Compare what your friends get. W: Well, we all get the same. But I have to buy all my music things as well things for school and have hardly anything left to spend on clothes. M: Right. Do you have to help around house? W: Not really. M: So you don't have to do anything for this pocket money. W: Mum said if I did that I will never have time to do my school work. M: Has she said you can have more pocket money when you are 15? W: Well, Mum just says she'll decide when I'm ready to have more. And I've just got to wait. M: Maybe you should sit down with her and say "How can I prove that I am old enough to get more?" W: So, I should talk to her again. M: Yes, but don't argue with her. Just discuss it calmly. W: OK, thanks. What was said before this conversation?
A: M: Are you OK, Lily? You don't look very happy.
[Q]: M: I couldn't make it last December. But I finally went there three months later. I plan to visit again next year. What was said before this conversation?
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[A]:
W: Did you go to Yellowstone Park for vacation last year?