Professor: Everyone should be here by now. Where’re they?

David: Well, there was a notice posted on the bulletin board, but maybe not everyone saw it.

Professor: Did anyone put up a notice in the regular classroom?

David: Well, I think nobody did.

Professor: Really?

David: I hate to say it, but I don’t think the rest of the class is coming.

Professor: It’s all my fault. I should have told them all on the last class.