sentences:  Unification can be achieved by incorporating into a single model the idea that the physical system (identified with phonetics) constrains the underlying abstract system (identified with phonology), making the units of control at the abstract planning level the same as those at the physical level.The plan of an utterance is formatted as a gestural score, which provides the input to a physically based model of speech production - the task dynamic model of Elliot Saltzman.The gestural score graphs locations within the vocal tract where constriction can occur, indicating the planned or target degree of constriction.