The national language of America is technically called English, stemming from the fact that the United States' first colonial settlers and our governmental forefathers were, you know, from England. But, as "Harry Potter" stars Daniel Radcliffe, Emma Watson, Rupert Grint and Tom Felton learned when they sat down with MTV News for a very special edition (OK, the only edition) of "American Talk With Josh Horowitz," there's a HUGE difference between proper English and what we speak -- and how we speak it -- in the States.

Dan, Emma, Rupert and Tom gamely took their best crack at employing an American accent to utter some quintessential Yank names, phrases and put-downs, including one of a certain other popular franchise. So how'd the "Potter" kids do? Let's just say that if they had to defeat Voldemort with the strength of their American accents alone, the Dark Lord would currently be kicking back with a nice 30-year-old Scotch, celebrating his domination of the world.

"Harry Potter and the Deathly Hallows: Part 1" hits theaters this Friday, November 19. Keep checking MTV Movies Blog for more of our Harry Potter Week coverage, including cast interviews, photo galleries, polls, top-10 lists, recaps of the first six films, and awesomely nostalgic flashback videos showcasing the cast from their early days.

Which "Harry Potter" cast member has the most believable American accent? Tell us in the comments!