The aim of this paper is to investigate the semantic expansion process of compound endings of the connective endings '-daga(다가), -go(고), -eoseo(어서), -goseo(고서) and the particle '-neun(는)' were combined. These compound connective endings signify the conditional meaning. And the meaning are derived from contrastive or exclusive meaning of the particle ‘-neun(는)’. These endings were differentiated from the simply combined forms ‘-daganeun, -goneun, -eoseoneun, -goseoneun’ by the syntactic and semantic characteristics. And These endings have the semantic characteristic that the following clause should be come negative content, also the syntactic characteristics that the front clause should be come the case marker ‘-i/ga(이/가)’ and the following clause should be come a declarative sentence or a interrogative sentence. If the following clause come an imperative sentence or proposal sentence, the sentence is not right. (Sungkyunkwan University)