The purpose of this study was to investigate whether or not Japanese children with specific language impairment (henceforth; SLI) would in fact experience difficulty with grammatical case-marking. The participants were 10 Japanese children with SLI, aged 7;7 to 11;4, and 25 Japanese children with typical language development (henceforth; TLD), aged 8;11 to 9;11. In this study, a sentence completion task was used, which involved both active and passive sentences with canonical and scrambled word order. The children with SLI were significantly less accurate than those with TLD with the use of grammatical case-markers. Moreover, the majority of the errors that the children with SLI made with case-marking consisted of canonical case-marking patterns. These results suggest that Japanese children with SLI do in fact appear to experience difficulty with grammatical case-marking and furthermore that they seem to rely on canonical case-marking patterns to compensate for their deficits.
