In this article, I argue that first language (L1), second language (L2) and third language (L3) acquisition are fundamentally the same process, based on learning by parsing. Both child and adult learners are sensitive to fine linguistic distinctions, and language development takes place in small steps. While the bulk of the article focuses on…

A recurring question in the literature of heritage language acquisition, and more generally of bilingual acquisition, is whether all linguistic domains are sensitive to input reduction and to cross-linguistic influence and to what extent. According to the Interface Hypothesis, morphosyntactic phenomena regulated by discourse-pragmatic conditions…

We study the learnability problem concerning the dative alternations in English (Baker, 1979; Pinker, 1989). We consider how first language learners productively apply the double-object and to-dative constructions ("give the book to library"/"give the library the book"), while excluding negative exceptions ("donate the…

The central claim in Amaral and Roeper's (this issue; henceforth A&R) keynote article is that everyone is multilingual, whether they speak one or more languages. In a nutshell, the idea is that each speaker has multiple grammars or "sub-sets of rules (or sub-grammars) that co-exist". Thus, rather than positing complex rules to…

This study investigates how derivational complexity interacts with first language (L1) properties, second language (L2) input, age of first exposure to the target language, and length of exposure in child L2 acquisition. We compared elicited production of "wh"-questions in French in two groups of 15 participants each, one with L1 English…

In this article we compare five groups of learners acquiring Dutch gender as marked on determiners and adjectival inflection. Groups of L1 (first language) children and L1-SLI (first-language specific-language-impairment) children are compared to three Turkish-Dutch L2 (second language) groups: adult L2, child L2 and child L2-SLI. Overall, our…

This study compares the linguistic knowledge of adult second language (L2) learners, who learned the L2 after puberty, with the potentially "eroded" first language (L1) grammars of adult early bilinguals who were exposed to the target language since birth and learned the other language simultaneously, or early in childhood (before age 5). I make…