This study investigated on the acquisition of Japanese noun-modifying clauses by Korean-Japanese bilingual children who attend Korean elementary schools. Focusing on its forms and meanings, the acquisition of Japanese noun-modifying clauses was analyzed by comparing the data of L1 infants and adult learners of Japanese(L2 learners). By comparing these data, this study aims to clarify the characteristics of Japanese as a heritage language. This study analyzes noun-modifying clauses in an oral interview data from 62 speakers of Japanese at three different ages and levels of proficiency.
First, this study analyzes whether the acquisition of noun-modifying clauses produced by Korean-Japanese bilingual children follows the Noun Phrase Accessibility hierarchy (NPAH), proposed by Keenan and Comrie(1977). The result revealed that even children of lower ages and lower proficiency used direct object(DO) and oblique(OBL) relatives, which suggests that subject relatives(SU) are not easier than DO or OBL relatives for the bilingual children. In result, the acquisition of noun-modifying clauses does not follow the NPAH.
Second, this study analyzes whether adjective-like noun-modifying clauses are easier to be acquired than the other types of clauses. The result shows that even children of lower grades and lower proficiency of Japanese used not only adjective-like clauses but also non-adjective like clauses. In result, it can not be said that adjective-like noun-modifying clauses are easier to be acquired.