According to David J. Peterson on, there's actually only one line in the Dothraki language in Season 3:

He did "twice as much work" for Season 3 as he did for Season 2. I assume that this means the bulk of his work was on the Low Valyrian of Slaver's Bay. I wonder if he's tackled Old Tongue yet.--The Dragon Demands (talk) 04:51, January 7, 2013 (UTC)