Achievement of an intended goal can be cancelled even after it is apparently asserted. One type of challenge to telicity is the phenomenon of event cancellation. The telic interpretation and event cancellation are mutually exclusive in the morphological causative construction and the causative cwu-construction, which provides a way to verify that the morphological causative verb may be interchangeable with the causative verb cwu on v without any meaning change. The terminal node v is split into two pieces (i.e., the verbalizing v with the causative feature and (a/e)cwu with the benefactive feature, which is known as "fission" within Distributed Morphology (Halle 1997, Noyer 1997). However, the morphological causative verb interchangeable with the causative verb cwu on v cannot appear with the benefactive suffix verb (a/e) cwu on v since the two phonologically identical verbs are ruled out by the filter *cwu-cwu at PF. At this point, the lexical verb on V cannot undergo raising to the causative morpheme on v to obey the constraint.