Hwang, Sun Hee. (2023). Exploring the use of -ese and -nikka by English-speaking learners on the basis of corpus-based learner data. The Lintuistic Association of Korea Journal, 31(3), 195-215. This study investigated how English-speaking learners of Korean use two causal connectives, -ese and -nikka, on the basis of comparison between the non-native speaker (NNS) corpus and native speaker (NS) corpus, and whether there is a relationship between learners proficiency level and error rate. A comparison analysis was conducted on the Korean Learners Corpus (KLC), and a native speaker corpus, the Sejong Corpus. It has been known that English causal connective because can be used in all three of Sweetsers (1990) content, epistemic, and speech act domains, but Korean tends to distinguish the use of causal connectives -ese and -nikka depending on those causal relations. The results indicate that native speakers perform differently in the choice between -ese and -nikka depending on causal relations, while L2 learners performance do not reach significance level. Especially for the epistemic causality, unlike native speakers, English-speaking learners use both -ese and -nikka at a similar rate. With respect to the error rate according to level of proficiency, the results reveal that the error rate decreases as proficiency level increases. This fact could imply that the complete acquisition of causal connectives is ultimately possible in principle despite L1-L2 different combinations of features into lexical items.