Why Neytiri Knows English
"You'll learn when you see the whole movie that the humans have been there for years now. They've been there a while. So this is not the first time that a human or an Avatar has made contact with them.
"If anything, Sigourney's character, Grace, has been connecting with them for a while now.
"There was a lot of learning - it was very much like Dances With Wolves where the natives learn from the outsider and vice versa. The only thing is that never before has a human penetrated as deeply as Sam's character does."