Verbal directionality and argument alternation in Dinka

The derivational morphology of verbs in Dinka includes a distinction between direction towards the deictic center (centripetal) and a direction not towards the deictic center (centrifugal). A goal adverbial requires a directional verb, and an object of such a verb refers to something that moves to(wards) an explicit or implicit goal. The object of a directional verb may play another role in the event described by the sentence than the object of the corresponding simple (and non-directional) verb. This gives rise to so-called argument alternation, in that, for instance, an object and an instrumental adverbial of a simple verb may correspond to, respectively, a goal adverbial and an object of the directional verb. Another type of argument alternation results from the possibility of expressing a goal as an object of an applicative verb with an intransitive or transitive base.