The theme of this volume, complexity, accuracy and fluency (CAF) as dimensions of second language production, proficiency and development, represents a thriving area of research that addresses two general questions that are at the heart of many studies in second language acquisition and applied linguistics: What makes a second language (L2)…

The research project reported in this chapter consists of three studies in which syntactic complexity, lexical variation and fluency appear as dependent variables. The independent variables are task complexity and proficiency level, as the three studies investigate the effect of task complexity on the written and oral performance of L2 learners of…

This chapter will present a research synthesis of a series of studies, termed here the Ealing research. The studies use the same general framework to conceptualise tasks and task performance, enabling easier comparability. The different studies, although each is self-contained, build into a wider picture of task performance. The major point of…

This paper examines the impact of task complexity on L2 production. The study increases task complexity by progressively removing pre-task planning time and increasing the number of elements. The combined effects of manipulating these two variables of task complexity simultaneously are also analyzed. Using a repeated measures design, 42…

Research into complexity, accuracy and fluency (CAF) as basic dimensions of second language performance, proficiency and development has received increased attention in SLA. However, the larger picture in this field of research is often obscured by the breadth of scope, multiple objectives and lack of clarity as to how complexity, accuracy and…

This chapter presents the results of a study on interlanguage variation. The production of four L2 learners of Italian, tested four times at yearly intervals while engaged in four oral tasks, is compared to that of two native speakers, and analysed with quantitative CAF measures. Thus, time, task type, nativeness, as well as group vs. individual…

This study investigated how task complexity affected native and non-native speakers' speaking performance in terms of a measure of communicative success (functional adequacy), three types of fluency (breakdown fluency, speed fluency, and repair fluency), and lexical diversity. Participants (208 non-native and 59 native speakers of Dutch) carried…

This paper reports a case study of the nature and extent of progress in speaking skills made by a group of upper intermediate instructed learners, and also assessors' perceptions of that progress. Initial and final interview data were analysed using several measures of Grammatical and Lexical Complexity, Language Accuracy and Fluency. These…