The first stage of combinatorial speech is better described as variable than uniform. Talk of variants obscures two different aspects of language (knowledge and use) and two different aspects of language development -- acquisition of the grammar (competence) and deployment of the grammar in speaking and listening (performance). Null subjects and…

In this article, we provide an overview of the last twenty years of research on Indigenous sign languages, deaf community sign languages, co-speech gesture, and multimodal communication in the Australian context. From a global perspective, research on sign languages and on the gestures that normally accompany speech has been used as the basis for…

This dissertation presents a series of case studies concerned with whether the signal in a given set of measurements that we take in the course of linguistic inquiry reflects grammatical competence or performance factors. We know that performance and competence do not always covary, yet it is not uncommon to assume that measurements that we take…

Scholars of language development have long been challenged to understand the development of functional categories. Traditionally, it was assumed that children's language development initially relies on lexical elements, while functional elements become accessible only at later periods; and that it is lexical growth which bootstraps grammatical…

The "wanna" facts are a classic Poverty of Stimulus (PoS) problem: "Wanna" is grammatical in certain contexts ("Who do you want PRO to play with?") but not others ("Who do you want who[strikethrough] to play with you?"). On a standard analysis, "contraction" to "wanna" is blocked by some…

Teachers and parents intuitively judge the 'level' of the child and the 'level' of the text and try to match them; they know that overestimation or underestimation of either will be met with restlessness or boredom. In this way, they have an empirical understanding of Vygotsky's ZPD--the zone of proximal development he envisioned as measuring the…

This paper investigates English-speaking children's acquisition of raising constructions (e.g. "John seems to Mary to be happy") and fnds an asymmetric effect of NP type on their comprehension: an improvement in performance is observed when a lexical NP is raised across a pronominal experiencer (e.g. "John seems to her to be…

An evaluation measure (EM) guides a learner's choice of grammar when more than one is compatible with available input. EM must be universal, so children receiving comparable input acquire comparable grammars. It must favor the choices children actually make. The theoretical shift from rule-based grammars to principles-and-parameter-based grammars…

It has long been recognized that there is a natural dependence between theories of knowledge representation and theories of knowledge acquisition, with the idea that the right knowledge representation enables acquisition to happen as reliably as it does. Given this, a reasonable criterion for a theory of knowledge representation is that it be…

This study examines the "ba" and "bei" constructions in Mandarin using data from the Tong corpus, a new multimedia longitudinal child language corpus. A unified aspectual account of the two constructions is proposed: both require telic predicates, and should thus correlate with the perfective rather than imperfective aspect for…

Many English-speaking children use plural nominal forms in spontaneous speech before the age of two, and display some understanding of plural inflection in production tasks. However, results from an intermodal preferential study suggested a lack of "comprehension" of nominal plural morphology at 24 months of age (Kouider, Halberda, Wood,…

Traditionally, acquisition of syntactic knowledge and the development of sentence comprehension behaviors have been treated as separate disciplines. This article reviews a growing body of work on the development of incremental sentence comprehension mechanisms and discusses how a better understanding of the developing parser can shed light on two…

To test between two recent accounts of the early stages in the acquisition of negation, we conducted an elicited production study with 25 children, between 2;05 and 3;04 (mean 2;11). The experimental study produced a robust set of negative sentences, with considerable individual variation. Although 13 of the child participants mainly produced…

Generative approaches to language have long recognized the natural link between theories of knowledge representation and theories of knowledge acquisition. The basic idea is that the knowledge representations provided by Universal Grammar enable children to acquire language as reliably as they do because these representations highlight the…

This dissertation explores parallels between Complementizer Phrase (CP) and Determiner Phrase (DP) semantics, syntax, and morphology--including similarities in case-assignment, subject-verb and possessor-possessum agreement, subject and possessor semantics, and overall syntactic structure--in first language acquisition. Applying theoretical…