Quote #36-

Wan Shi Tong: (to Katara; preparing to fight him as she is being chased) Your waterbending won't do you much good here. I have studied Northern Water Style, Southern Water Style, even Foggy Swamp Style.

(Sokka smashes a book against Wan Shi Tong's head, causing him to collapse)

Sokka: That's called Sokka Style! Learn it!