What do Japanese and Korean Have in Common?

Abstract. Many of the verb endings of modern Japanese and Korean have been created by contracting structures that consist of the stem + attached strings of particles and auxiliaries. Most of the auxiliaries have been taken from free verb stems that were grammaticalized for special purposes. Though the paradigmatic systems grew independently in the two languages, many of the ingredients go back to a common source that we can reconstruct on the basis of their shapes and meanings. Korean and Japanese share certain configurations of meaning and grammar, such as the well-known marking of focus, that are realized by markers which are not directly cognate in these structures but can be seen as cognate with forms in other structures within each language. These two languages have much more in common with each other than either has with any other language. This is why we think it is possible to reconstruct a prehistoric ancestor that can be called proto Korean-Japanese.