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 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…

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…

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…

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…

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…

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…

Active learning is recognized as an instructional approach that engages students in active participation and encourages them to reflect on the learning process. This research study aimed to investigate the effectiveness of implementing active learning in the "English at Work" course and to explore EFL undergraduate students' attitudes…

The present study aimed to explore the potential moderating effect of foreign language anxiety (FLA) on the relationship between second language (L2) competence and willingness to communicate (WTC) in 129 Chinese study-abroad English learners in Belgium. Descriptive analyses revealed fairly low levels of FLA and high levels of WTC of the…

In recent years, Third Language Acquisition (TLA) in Cross-Linguistic Influence (CLI) research has been debated regarding background languages' impact on learning a target language. While Second Language Acquisition (SLA) research often emphasizes the primary influence of the first language (L1) on the target language, it does not discount the…

Learner corpus research has expanded from focusing primarily on English as a second language (L2) to include languages such as L2 Spanish, reflecting the growing importance of corpus linguistics in second language acquisition (SLA) research. In this context, and because prompts are the means by which learner corpora gather their texts, it has…

Second-language (L2) knowledge of English is an essential communication tool in the contemporary era of globalization in many research and business fields. Among the important tasks in English education is the measurement of student proficiency. While various tests purport to measure proficiency in learning English, repeated preparation and…

Lexical frequency benchmarks have been extensively used to investigate second language (L2) lexical sophistication, especially in language assessment studies. However, indices based on semantic co-occurrence, which may be a better representation of the experience language users have with lexical items, have not been sufficiently tested as…

This study examined the influence of cognate status and language distance on simultaneous bilingual children's vocabulary acquisition. It aimed to tease apart effects of word-level similarities and language-level similarities, while also exploring the role of individual-level variation in age, exposure, and nontarget language proficiency. Children…