Joel H,
I just read your comment and looked at "The Stanley Parable". I think this would work just fine in a first person exploratory game. As I've thought it about this and games more, I can't think of a game type this wouldn't work in, actually.

First person mode would be interesting in the thoughts could switch from initially being in the native language but switching to the new language as progress is made. That's sort of the ideal situation I suppose in general. If you can think in the new language I suppose you've won.