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…

In natural language, evidence suggests that, while some rules are productive (regular), applying broadly to new words, others are restricted to a specific set of lexical items (irregular). Further, the literature suggests that children make a categorical distinction between regular and irregular rules, applying only regular rules productively…

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…

The goal of language comprehension for humans is not just to decode the semantic content of sentences, but rather to grasp what speakers intend to communicate. To infer speaker meaning, listeners must at minimum assess whether and how the literal meaning of an utterance addresses a question under discussion in the conversation. In cases of…

The Phonological Permeability Hypothesis (PPH, Cabrelli Amaro & Rothman, 2010) attempts to reconcile evidence suggesting some L2 learners, however rare, attain native-like L2 phonological systems with the observation that most do not. Considering existing L2 phonology research, it is not clear that phonological differences between early and…

This study contributes to current trends of heritage speaker (HS) acquisition research by examining the syntax of psych-predicates in HS Spanish. Broadly defined, psych-predicates communicate states of emotions (e.g., to love) and have traditionally been categorized as belonging to one of three classes: class I--"temere" "to…

The purpose of this dissertation is to empirically test the hypothesis that children's omission of functional elements reflects performance factors (McKee, 1994; McKee & Iwasaki, 2001), rather than lack of knowledge (Felix, 1987; Radford, 1990, 1995; Tomasello, 2000). The multi-level production system treats content and function morphemes…

While normal child language acquisition results in complete productive and comprehension abilities at a relatively young age, adult language acquisition is more belabored and often results in linguistic abilities that differ from those of native speakers in terms of both productive and comprehension abilities. A major line of research in language…

How bilinguals' two languages interact with each other has stimulated considerable research. However, little of this research has focused on objective measures of speech production. This study aims to investigate bilinguals' production of Guoyu and Taiwanese voiceless sibilant fricatives to see how language contact and language dominance influence…

This thesis aims to examine the development of morphosyntax with longitudinal English production from Diany, a Mandarin-speaking child, starting from the second week Diany arrived in the U.S.A. (age 4;9). The study is particularly interested in whether Diany's acquisition of verbal morphemes and verb movement supports relevant hypotheses in the…

This longitudinal study examines the acquisition of tense and agreement morphology by child L2 learners in an early stage of language acquisition. The objectives of this study are twofold. The first is to observe the development of verb inflections and syntactic competence over time from an early stage by Chinese child L2 learners of English. The…