Chapter 3. The acquisition of generic null subjects under the Borer-Chomsky conjecture

Abstract

This chapter examines how Brazilian Portuguese (BP)-speaking children acquire a critical property associated with partial null-subject languages, generic null subjects. The purpose is to investigate whether the data about the acquisition of generic null subjects are compatible with the idea that parametric variation is caused by the cross-linguistic distribution of features in functional heads (known as the Borer-Chomsky conjecture). To acquire the distribution of (null) subjects, the child should pay close attention to ϕ-features on T and D. Studies have shown that children become sensitive to the presence of verbal inflections and determiners before their first words (Dye et al., 2019), which leads to the prediction that children should not show evidence of parameter misssetting. We found that generic null subjects emerge as early as 1;9 in BP, which is consistent with the prediction of early parameter setting. However, generic null subjects did not appear frequently in spontaneous production and they increase as the child grows older. As generic null subjects are used to talk about rules, patterns and generalizations, not about specific individuals, the production of generic null subjects increases as children’s conversational topics become less egocentric.