Toph:
Good morning, Earthbending student!
Aang:
Good morning, Seefu Toph.
Katara:
Hey, you never called me Seefu Katara.
Aang:
Well, if you think I should...
This quote occurs at 00:01:52-00:02:04 in the video.
Aang begins to learn earthbending from Toph; Uncle Iroh resumes teaching Zuko firebending to better prepare him for facing Azula, and reveals a new technique he learned from watching waterbenders.