听力原文:W: Well, this must be the National Library. M: I guess so. Oh no! I don't think it's open today. Look. It says 'Closed Tuesdays'. W: Well, we'll just have to come back tomorrow. M: But we're supposed to go on that tour tomorrow. W: Oh, that' s fight. I forgot all about it. How about the day after tomorrow then? M: It's OK with me. When will they visit the National Library?