Korean has so-called after-thought or right dislocation constructions. But wh-words can not be the target of the construction. This paper proposes that the ban on wh-after-thought arises from PF side, especially sentence final intonation. If wh-words are after-thoughted, the sentence final ending C require y/n-question sentence final intonation but the Ω head which is onto C projection and hosts after-thoughted wh-words requires wh-question sentence final intonation. So, the sentence final intonation (= C intonation + Ω intonation) has paradoxical information and the expression crashes at PF. This proposal naturally can be extended to describe the grammatical variation which says that some speakers accept wh-after-thought as grammatical when some, but not all, wh-words are after-thoughted in multiple wh-constructions. The main point is that there is some variation on whether all wh-words must match with sentence final intonation or not.

• 이정훈(서강대학교)