Every week I have to teach a 40 minute teacher's class. About 3 teachers show up every time, and all are really good at English. (Well, one of them isn't quite as good as the other two, but compared to other Koreans, she is pretty good.) Last semester, I just used lessons I found online that revolved around newspaper articles and conversation questions. This semester, I'd like use a book. Does anyone have any good recommendations for a book? (I'm looking for one that teaches some advanced grammer.) Any help would be greatly appreciated!