What do we learn about Bill?

M: Did Bill really have his two wisdom teeth pulled out?
W: Yes, his dentist suggested that he should because he had suffered a great deal of toothache since last September.
M: Oh, good. He won’t be bothered by them again.

W: I feel sorry for my brother. He’s really under stress.
M: Why is that?
W: He’s trying to get into the country’s top engineering school and I’ve never seen anyone study so hard. He hardly sleeps at the moment.
M: Well, the competition to get in there is absolutely fierce.