I had a lesson with the single worst student I've ever encountered here. You know, I work at an English Conversation school. People pay waaaay too much money to come and practice their conversation skills. So imagine my chagrin at a private lesson that started like this...

Sam (in extra-cheerful voice): "Hello! How are you today?"
Student (in flat voice with slight frown): "Hello."
Sam: "How was your job?"
Student: "..."
Sam: "Uh, did you work today?"
Student: "... m."
Sam: "What happened?"
Student: "..."
Sam: "Work bad?"
Student: "..."
Sam: "Work busy?"
Student: "..."
Sam: "Work good?"
Student: "... m. Good."
Sam: "...Okay."

This went on for another 37 minutes. Not that I was counting.