The purpose of the present study is to provide a comprehensive account of English and Korean light verb constructions, focusing on the role of predicate nominals. Given that English predicate nominals have the base verb form and Korean predicate nominals are Sino words, it will be argued that they belong to a mixed category of a verb and a noun, thus assigning theta roles to their arguments. Furthermore, it will eventually be concluded that predicate nominals have different degrees of specification of verb-hood and noun-hood, and this difference in specification can account for many well-known problems of the constructions.