Hi-Sun Helen Kim (University of Chicago) and Sang-Seok Yoon (University of Minnesota). 2009. Grammaticalization of Korean Connective NI & NIKKA and the Role of - KKA . Language Information. Volume 10. 45-71.
The aim of the paper is to investigate the grammaticalization process and the semantic shift involved in the development of the Korean causal connective - nikka . The two general semantic and pragmatic functions of - ni and - nikka are to mark temporal sequence and causality. In present day Korean, the causal meaning of ？ nikka prevails and it continues to grammaticalize, while the dominant use of ？ ni is limited to usages with tense and aspect markers or defective nouns.
Looking at the characteristics and origin of ？ kka , we propose that the roles of ？ kka in ？ nikka are to represent the speaker’s subjectivity, knowledge, justification, belief, and assertion; and to invite the co-alignment of the interlocutor. Furthermore, we speculate that ？ kka originated from a discourse marker which carried such functions. That is, as the causal ？ ni and the marker that grammaticalized into the morpheme ？ kka , have been used so frequently that the two forms eventually joined to become the connective ？ nikka .
Keywords: grammaticalization, causal connective, -ni, -nikka, sentence ender, discourse marker, pragmatics