Minority languages in diglossic situations with a majority language face the danger of eventual loss of vitality. The first sign of this is when child language acquisition begins to erode. This dissertation investigates the intergenerational transmission of the Isan language, spoken in the Northeastern region of Thailand. While the Isan community…

Recent research in the areas of second language testing and learner corpus research has provided increased insight into linguistic features of various score levels and into the meaning of a test score (Cushing, 2017; Knoch & Chapelle, 2018). However, language testing researchers have asserted the need to select linguistic features that are…

Learning new languages is a complex task involving both explicit and implicit processes (i.e., that do/do not involve awareness). Understanding how these processes interact is essential to a full account of second language (L2) learning, but accounts vary as to whether explicit processes help (e.g., DeKeyser, 2007), hinder (e.g., Ellis &…

Growing up in the digital era, young children are exposed to numerous educational applications and programs, some with well-designed curricula and others focused more on entertainment or game-like qualities. With the increasing popularity of mobile language-learning applications among young children, this dissertation raises a crucial question: do…

Language is inherently variable, and learner language is particularly variable. The variationist paradigm considers learner language a heterogeneously variable yet inherently rule-governed system. Specifically, learners' alternation between native-like and nonnative-like variants of a variable or invariable target native speaker (NS) form…

Generalization is the ability to apply regularities to novel instances, for example, correctly guessing that the plural for the novel English word 'wug' should be 'wugs'. Early language learners make overgeneralization errors like 'mouses', applying regularities beyond their attested uses. Theories concerned with the question of how learners learn…

While language aptitude and motivation are considered to be important contributors to second language (L2) attainment, two major gaps in the past research have been (1) a lack of nonlinear models stemming from a naive and tacit assumption that learning outcomes are linearly related to their predictors, and (2) a lack of unified and integrative…

This dissertation investigated how a bilingual's experiences can affect how their first language pronunciation can differ from monolingual speakers of their two languages. We used a methodology incorporating quantitative phonetic measurements of voice onset time and vowel formants, grammar and vocabulary tests, and qualitative measures of language…

Second language (L2) writing has been determined to be influenced by what is read, with language learners tending to borrow words and short phrases from input texts while writing (e.g., Wang & Wang, 2015). This phenomenon is referred to as lexical alignment. Only one empirical study has investigated the influence that the linguistic complexity…

Under the framework of item response theory (IRT) and generalizability (G-) theory, this study examined the effects of item difficulty on rating reliability and construct validity on both the constructed-response (CR) items and essay items on English examinations. The data collected for this study were students' scores and responses on the two…

This manuscript-based dissertation is comprised of three interrelated longitudinal studies on Spanish language growth and deceleration and its impact on English language growth and English reading skills in bilingual children. Chapter 1 introduces the manuscript-based dissertation and provides the background on existing, longitudinal work of dual…

This research project sought to explore the influence of English L2 on Spanish L1 in an environment where the L1 (Spanish) is the dominant language. Participants were recruited through voluntary response sampling at the University of Puerto Rico Secondary School (UHS). They completed a language survey on Google Forms that collected general…

Children born preterm constitute one of the largest populations of children at risk for the development of language impairments. A little over one in ten pregnancies result in a preterm birth and approximately 25% of these children go on to experience subsequent difficulties with language (CDC, 2015; Foster-Cohen, Friesen, Champion, &…

Recent research has demonstrated that L2 learners and heritage speakers might have two different profiles in terms of their syntactic, morpho-syntactic, and lexical-semantic knowledge of a target language (Montrul, 2004, 2006, 2010; Montrul, Foote, & Perpinan, 2008). However, the most influential of the major studies have been limited to…

Many people want to learn a foreign language, but issues of time, convenience and cost mean that classes are often insufficient for learners, and increasingly learners are supplementing or replacing their classroom learning with online learning. The majority of existing online language learning systems use the traditional grammar-translation…