Complex sentence: Ghostface is rarely depicted as speaking while physically on screen to aid in concealing the identity of the character behind the mask, except for grunts and groans when injured which are dubbed into the film during the editing phase by Jackson.
Split into simpler sentences: Ghostface is rarely depicted as speaking while physically on screen, in order to aid in concealing the identity of the character behind the mask. Exceptions to this are grunts and groans when injured, which are dubbed into the film during the editing phase by Jackson.