Subject-verb agreement in German in bilingual children with and without SLI

We investigated the acquisition of subject-verb agreement (SVA) in German based on spontaneous speech data from both typically developing (TD) and language-impaired (SLI) children learning German as a second language (L2), and from language-impaired monolingual children. Rothweiler et al. (2012) suggested that SVA is vulnerable in SLI. The intent of our study was to determine whether TD child L2 learners (cL2) in contrast to children with SLI do not have difficulties with SVA. Many studies report that cL2 acquisition can differ from monolingual (L1) acquisition and that the differences look similar to those of impaired L1 learners, which makes it difficult to distinguish cL2 learners who have SLI from those who do not. If such similarities were to be found in the acquisition of SVA in the two bilingual groups, SVA would be ruled out as a possible marker of SLI in cL2 learners. Three groups of children were compared: six Turkish-German early cL2 learners without SLI, and twelve children with SLI - six monolingual German children and six Turkish-German early cL2 learners. As in Rothweiler et al. (2012), all children were advanced learners and were therefore expected to have acquired SVA. We found that the unimpaired early cL2 learners had indeed successfully acquired SVA. In contrast, neither the monolingual nor the bilingual children with SLI succeeded in reliably producing correct SVA.