Problem: Given the question: W: Thank you very much, but I am going to the theater that evening. What was said before this conversation?
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The answer is:
M: Would you like to have dinner with me on Saturday?

Problem: Given the question: W: I'll see you in the library, then. What was said before this conversation?
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The answer is:
M: My grades are not bad, but not good enough. I know I didn't study at all this semester. Now I have to work very hard next semester to keep my scholarship.

Problem: Given the question: M: It's 8:30. W: Your watch is 10 minutes slow. There're only 5 minutes left for the speech. We're going to be late. M: Let's go for it right now. What was said before this conversation?
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The answer is:
W: What time is it?