Why can’t the woman go with the man?

M: I’m a little tired, so I think I’ll go to the student lounge and listen to a little music. Would you go with me?
W: I’d love to. But I have to go to the library to look at a book on reserve.

M: I was Sorry to hear about Bill’s being red. I know he was sick a lot and that he usually went to work late.
W: Oh, it wasn’t that. Bill made a big error in last month’s accounting.