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…

This study examined the impact of the manipulated task complexity (Robinson 2001a, 2001b, 2007, 2011; Robinson & Gilabert, 2007) on second language (L2) speech comprehensibility. I examined whether manipulated task complexity (a) impacts L2 speech comprehensibility, (b) aligns with L2 speakers' perception of task difficulty (cognitive…

This paper traces 9 non-English major EFL students and collects their oral productions in 4 successive oral exams in 2 years. The canonical correlation analysis approach of SPSS is adopted to study the disfluencies developmental traits under the influence of language acquisition development. We find that as language acquisition develops, the total…

It is a good practice to try to understand matters at hand by first stepping back and adopting an historical perspective, which I will begin this review by doing. Next, I will take up the challenges that each of the authors in the articles in this volume has presented for the study of complexity, accuracy, and fluency (CAF) in second language…

This article critically scrutinizes a number of issues involved in the definition and operationalization of complexity, accuracy, and fluency (CAF) constructs. It argues for maintaining clearer distinctions between CAF, on the one hand, and notions such as linguistic development and communicative adequacy, on the other. Adequacy, in particular,…

SLA researchers agree that explicit knowledge and learning play an important role in adult L2 development. In the field of cognitive linguistics, it has been proposed that implicit and explicit knowledge differ in terms of their internal category structure and the processing mechanisms that operate on their representation in the human mind. It has…

In this article, we examine current practices in the measurement of syntactic complexity to illustrate the need for more organic and sustainable practices in the measurement of complexity, accuracy, and fluency (CAF) in second language production. Through in-depth review of examples drawn from research on instructed second language acquisition, we…

What is second language fluency? What is a foreign accent? Is it possible for an adult second language learner to speak fluently with a heavy accent or vice versa? What factors contribute to the perception of fluency and a foreign accent? What acoustic attributes correlate with the perception of fluency and a foreign accent? To answer these…

Complexity, accuracy, and fluency have proved useful measures of second language performance. The present article will re-examine these measures themselves, arguing that fluency needs to be rethought if it is to be measured effectively, and that the three general measures need to be supplemented by measures of lexical use. Building upon this…

This study puts the Cognition Hypothesis (Robinson 2005) to the test with respect to its predictions of the effects of changes in task complexity ([plus or minus] few elements) and task condition ([plus or minus] monologic) on L2 performance. 44 learners of Dutch performed both a simple and a complex oral task in either a monologic or a dialogic…

Stuttered sentences pronounced by 12 4- to 6-year-old children in spontaneous conversation were analyzed for length and grammatical complexity. Results indicated that sentences in which stuttering occurred within the first three words were significantly longer and more complex than sentences where no fluency failure was found. Implications for…