Toph’s instructing abilities come into question when Aang cannot seem to overcome a block that keeps him from earthbending. Sokka gets himself in a jam, while befriending what was, moments before, his next meal, and Iroh and Zuko begin training utilizing new philosophies and methods that originate from the other elements.
Avatar: The Last Airbender 2×09 “Bitter Work”
https://trakt.tv/shows/avatar-the-last-airbender/seasons/2/episodes/9 (https://www.frederickcalica.com/?p=3344729)