When Carla's brother hits Turk, he swings left to right (his) and Turk falls to the left (Turk's). This means that Turk's black eye from the fight should be on the right, but for the rest of the episode it is his left eye that is black.
Marco said he just learned English a few years ago; any adult ESL student would speak English with a native accent, however Marco speaks perfect US English with none of his native accent.