Jang Yoon-hee. 2002. Some Remarkable Changes in the History of Korean Verbs. Korean Semantics, 10. The most remarkable changes in the history of Korean verbs are the change of stem and usage of some verbs. First, the most noteworthy changes in verb stems include unification of verb stems which were formerly doublets, levelling of allomorphs of verb stems, restructuring of verb stems, change in the way of word formation, addition to existing verb stems, and so on. Among these, especially, restructuring of verb stems is the result of various events. which include phonological changes, restructuring due to reanalysis of verb stems, and lexicalization of morphological constructions. Secondly, the change of usage of some verbs is related to the change of intransitive verbs, transitive verbs, and verbs which were used either as an intransitive or a transitive verb. The most remarkable change in intransitive verbs consists in psychological verb construction. Many psychological verbs in Middle Korean had disappeared, and the construction of ‘psychological adjective + ha’ took over its place. In Middle Korean, some verbs were used both as intransitive and transitive verbs. Moreover, more often than in Modern Korean, some verbs which were mainly used as adjectives were used also as intransitive verbs. Among the constructions with ‘- ti-’ combined with intransitive verbs in Middle Korean, some expressed the meaning of agent's intention and some expressed the passive meaning. And in Middle Korean, we can find some verbs which could be used either as transitive verbs or adjectives, or which had argument structures different from those of Modern Korean. Especially, the ‘-a/ is-’ construction combined with transitive verbs could express passive meaning. Lastly, there were more verbs in Middle Korean which were used as both intransitive and transitive than in Modern Korean.