Studies on cross-linguistic influence (CLI) in third language (L3) acquisition of morphosyntax have predominantly used offline tasks to determine which language(s) constitute the source of CLI. Yet, they provide little evidence about incremental processing of morphosyntactic features that are similar to participants’ first language (L1) and/or second language (L2). Therefore, we conducted an eye-tracking study with Polish–English bilinguals ( n = 41) who were taught a miniature version of Norwegian in a laboratory setting. Participants were presented with sentences testing adjectival number agreement (a feature present in Polish and Norwegian, but absent in English) and indefinite articles (present in English and Norwegian, but absent in Polish). The results showed a complex pattern of both facilitative and non-facilitative transfer effects from the L1 and the L2, thus providing evidence for property-by-property models of L3 syntax.
Skałba et al. (Wed,) studied this question.