The current project investigates developmental aspects of acquiring locative verb constructions in English as a second language. Locative verbs, such as to pour, to spill, to spray, and to sprinkle, constitute a prototypical case of an overgeneralization problem in language learning: Whereas some of the verbs can appear in two alternative constructions (e.g., John sprayed water onto the plant vs. John sprayed the plant with water), others are restricted to a single frame (e.g., John poured juice into the glass) and are perceived as unnatural when used in the alternative structure (e.g., *John poured the glass with juice). How do language learners acquire the alternation patterns, and, at the same time, avoid overgeneralizations? In contrast to the depth and diversity of child language investigations (e.g., Ambridge, Pine, & Rowland, 2012; Gropen, Pinker, Hollander, & Goldberg, 1991a, 1991b), only a handful of research projects examined acquisition of the locative semi-regularities in L2 producing contradictory and largely irreconcilable proposals. The dissertation critically reviews methodological, theoretical, and empirical underpinnings of the conflicting claims, recasts the problem of learning locative semi-regularities within the MOGUL (Modular Online Growth and Use of Language) framework (Sharwood Smith & Truscott, 2014; Truscott & Sharwood Smith, 2004), and proposes an alternative processing-based account of how real-time encounters of the target constructions relate to the developmental transitions in language learners' grammatical representations.

The study tested predictions of the alternative proposals in two empirical investigations. One hundred and two native speakers of Mandarin Chinese learning English as a second language (of low, intermediate, and high L2 proficiency levels) and a comparison group of English native speakers (n=50) took part in an acceptability judgment task (Experiment 1) and an eye-tracking study using visual world paradigm (Experiment 2). Results revealed complex but consistent patterns in participants' performance. All experimental groups demonstrated both target-like performance and diverged from the assumed target language standards. These findings suggest that any property theory relying on specifications of what L2 learners know (or fail to know) at different stages in L2 development (Gregg, 2008) would face considerable challenges in explaining the observed behavioral patterns. At the same time, the results can be naturally understood within a dynamic framework allowing an integration of the property-theoretical constructs with the mechanisms explaining real-time changes in the linguistic system.