On null-subject languages and the Overt Pronoun Constraint: A comparison of English, Mandarin and Japanese

This study reports on findings from two experiments investigating the interpretive patterns of overt pronouns in an embedded subject position with three types of matrix subjects (i.e. a referential NP, a quantified NP, or a wh-phrase) in Mandarin, English, and Japanese. According to the Overt Pronoun Constraint (OPC), overt pronouns in null-subject languages cannot have bound-variable interpretation, i.e. they cannot be bound by a quantified NP or a wh-phrase. This constraint has been assumed to be universal and accessible for learners at early stages of second language (L2) acquisition. The results of Experiment 1 show that, although Mandarin is a null-subject language, Mandarin and English native speakers as well as L2 learners of both languages demonstrated similar patterns of interpretation, accepting both coreference readings and bound-variable readings, the latter being contrary to the prediction of the OPC. The results of Experiment 2 show that Japanese native speakers differed from Mandarin native speakers in that the former accepted both coreference readings and bound-variable readings at chance levels. These findings clearly demonstrate that the OPC cannot be characterized as a property of null-subject languages generally, given the lack of effect in Mandarin, and there are cross-linguistic variations in interpretive patterns for overt pronouns among languages that exhibit the effect.