用所给句子完成对话。 A. What about you? B. I can't leave before nine. C. What time shall we leave? D. Yes, I think so. E. We won't leave before nine. F. What about going for a walk? A: Are you free tomorrow? B: __ 1 __ A: What shall we do then? B: Let me see. __ 2 __ A: Good idea. Shall we ask Jim? B: OK! __ 3 __ A: Well, __ 4 __ I have a lot of work to do. B: Don't worry. __ 5 __ We'll wait for you as usual.