According to the PF merge hypothesis on the formation of inflected verbs in Korean (J. H.-S. Yoon 1993, 1994, 1997, Park 1994, J.-M. Yoon 1996, among others), so-called pre-final and final verbal endings independently project at syntax, and merge with the head of the preceding phrase at PF. One consequence of this hypothesis is that a predicate, i.e., a verb stem aug- mented with inflectional endings, is not a constituent at syntax. Chung (2009a, 2011) attributes some syntactic behaviors (immobility and undelet- ability) of embedded predicates to the very non-constituent status of predicates. This paper discusses two types of apparent challenges for the PF merge hypothesis: (I) Predicates in certain constructions appear to be syntactically active; and (II) a string of elements that is defined as a constituent ? la the PF merge hypothesis appears to be syntactically inert. It will be demonstrated, however, that neither type of challenges necessarily disproves the PF-merge hypothesis: As for the type (I) challenges, there are alternative derivations available; and as for the type (II) challenges, the syntactic inertness comes from independently motivated morphological requirements.

• 정대호(Hanyang University) | Dae Ho Chung