This article presents a theoretical review of and methodological guidelines for the study of two key notions in second language acquisition research, complexity and difficulty. The term "complexity" has gained considerable currency over the past decades and has taken on a wide range of meanings. We argue for a more restricted…

This study examined the influence of linguistic input on the development of productive and receptive skills across three fundamental language domains: lexico-semantics, syntax, and phonology. Seventy-one (35 female) Basque-Spanish bilingual children were assessed at three time points (Fall 2018, Summer 2019, Winter 2021), between 4 and 6 years of…

This dissertation is a quantitative analysis of language proficiencies through the lens of the dynamic model of multilingualism, using survival analysis to evaluate time until thresholds of foreign language proficiency are reached and nonparametric tests (Wilcoxon signed rank and Kruskal-Wallis) to compare proficiencies at distinct time intervals…

Key Findings: This study identifies a strong positive relationship between digital literacy and language proficiency, highlighting how technological competence enhances motivation, engagement and PL, leading to improved language learning outcomes. Purpose: This research explores the connection between digital literacy and language proficiency,…

In the last decades, the field of applied linguistics has called for an expanded knowledge on language learning in different learner groups and contexts, including forced migrants and low-literate learners. This article focuses on an under-studied learner group in an under-studied context: low literate adult refugees (LESLLA) subjected to language…

It is widely accepted that written corrective feedback (WCF) is an effective tool for helping learners develop their L2 knowledge. Yet, it remains inconclusive as to which type of WCF can best facilitate L2 learning. In recent years, many second language acquisition (SLA) researchers agree that "direct" and "focused" WCF may be…

This study examines whether children acquiring Tseltal (Mayan) demonstrate a noun bias -- an overrepresentation of nouns in their early vocabularies. Nouns, specifically concrete and animate nouns, are argued to universally predominate in children's early vocabularies because their referents are naturally available as bounded concepts to which…

The current study set out to examine to what degree age of acquisition (AOA), defined as a learner's first intensive exposure to a second language (L2) environment, mediates the final state of postpubertal, spoken vocabulary attainment. In Study 1, spontaneous speech samples were elicited from experienced Japanese users of English (n = 41) using…

Longitudinal research on language abilities and social functioning in young children suggests that gains in one domain affect gains in the other. However, few studies have examined inter-relations of language and social functioning jointly among young children diagnosed with autism spectrum disorder (ASD). Pre-verbal toddlers with ASD are a group…

Students who have remained classified as English Learners (ELs) for more than six years are often labeled "Long-term English Learners" (LTELs). The present study examined the English Language Development (ELD) test scores and demographic information in a group of 560 students identified as LTELs. Despite assumptions that these students…

This systematic review addresses the research gap in understanding the efficacy of experimental interventions designed to improve the academic outcomes of English Learners with Learning Disabilities (ELswLD). After conducting a rich evaluation of reviews related to English Learners and to students who have disabilities, we contextualize the need…

C-Test is a gap-filling test designed to measure first and second language proficiency. Over the past four decades, researchers have shown the fit of C-Test data to parametric item response theory (IRT) models, but no study so far has shown the fit of C-Tests to nonparametric IRT models. The purpose of this study is to contribute to the ongoing…

Purpose and Method of Study: Using a phenomenological approach, this study explored in-depth the lived experience of United States Military Academy (USMA) cadets participating in a semester abroad program (SAP) to increase knowledge of how such experiences impacted their intercultural effectiveness development. This study added to the knowledge…

This study investigates the developmental trajectory of progressive construction among Chinese and Japanese EFL learners through a usage-based approach. A total of 600 written essays, produced by EFL learners from China and Japan with proficiency levels ranging from elementary to upper-intermediate, were analyzed. The findings reveal that advanced…

This study explores the integration of advanced AI technologies, including emotion detection and adaptive learning systems, to enhance second language acquisition among 274 English as a Foreign Language (EFL) learners. Utilizing a pretest-posttest randomized control trial, the research evaluates the effects of AI-enhanced interventions on…