Problem: Given the question: M: I'd be glad to. What was said before this conversation?
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The answer is:
W: If you have time, will you mail a letter for me tomorrow?

Problem: Given the question: W: Yes, it was wonderful. I particularly like the works by Da Vinci. M: I wish I had gone but I heard we had to wait for two hours to get the ticket. What was said before this conversation?
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The answer is:
M: Did you go to the Italian High-tech Exhibition in Tianjin University last month?

Problem: Given the question: W: Don't worry, Doctor. I want to be free as quickly as I can. What was said before this conversation?
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The answer is:
M: Mrs. Smith, you must take two pills every four hours without fail. And don't forget to finish the bottle.