Language proficiency is multi-componential in nature and, according to many SLA researchers and L2 practitioners, is best captured by the concepts of complexity, accuracy, and fluency (CAF). Two of the three studies reported in this paper adopted the Cognition Hypothesis (Robinson, 2003) as the means to address the question of whether increasing…

An important question in the field of English language teaching and learning is 'What is the relationship between research and second language (L2) instruction?'. A second question is 'What should the relationship be?'. This keynote speech explores these two questions. The speech provides a general overview of some of the important insights that…

In vocabulary research there has been a shift from focusing on single words to considering multiword sequences, such as collocations. Despite the general consensus among language researchers that collocation is essential to effective language use in real-world communication, particularly oral communication, language-testing researchers have made…

Most studies on task-based language learning focus on the oral performance of advanced level learners of English as a second language (ESL), while little research examines the written performance of beginning language learners in non-ESL contexts. This exploratory study aims to address this gap, by examining the effect of pre-writing tasks on…

Communicative adequacy is a key construct in second language research, as the primary goal of most language learners is to communicate successfully in real-world situations. Nevertheless, little is known about what linguistic features contribute to communicatively adequate speech. This study fills this gap by investigating the extent to which…

This longitudinal case study follows a dynamic systems approach to investigate an under-studied research area in second language acquisition, the development of complexity and accuracy for an advanced untutored learner of English. Using the analytical tools of dynamic systems theory (Verspoor et al. 2011) within the framework of complexity,…

The triad dimensions of complexity, accuracy, and fluency (CAF) has been widely used for assessing second language performance and development. Unlike accuracy and fluency, the construct of Chinese syntactic complexity has not been comprehensibly conceptualized or operationalized. Moreover, not tailored to the typological differences such as the…

This study employed synthetic and meta-analytic techniques to review the literature on the Cognition Hypothesis, which predicts that increasing task complexity influences the quality of second language production. Based on 8 inclusion criteria, 17 published studies were synthesized according to key features. A subset of these studies (k = 9) was…

This study investigates the combined effects of task-based careful online planning and the storyline structure of a task on second language performance (complexity, accuracy and fluency). Sixty intermediate EFL learners were randomly assigned to four groups (n = 15). Participants were asked to perform two tasks with different degrees of storyline…

The purpose of this dissertation was to examine the relationships between working memory (WM) and three commonly used learning strategies or conditions in the nature of proficiency among adult L2 Russian learners. Based on the aptitude-learning condition interaction framework articulated by Robinson (2002b), the study identifies two types of…