Williams and Burden's (1997) social constructivist model outlines four aspects of the teaching-learning process, i.e., teachers, learners, tasks, contexts. Theorists and researchers have presented the same framework in slightly different ways. The strategies a learner uses and the effectiveness of these strategies very much depend on the learner him/herself (e.g., attitudes, motivation, prior knowledge), the learning task at hand (e.g., type, complexity, difficulty, and generality), and the learning environment (e.g., the learning culture, the richness of input and output opportunities). Language learning in general and vocabulary acquisition in particular are such problem-solving tasks at different levels of complexity. This problem-solving process is constrained by the learning context where the problem is being tackled. When a person approaches a relatively challenging task, s/he adopts certain strategies to solve the problem. Person, task, context, and learning strategies It is argued that despite the impressive amount of recent research on vocabulary acquisition, a person-task-context-strategy perspective that is presented here is needed in order to anchor existing research in a larger framework and to point to areas for future efforts. To this end, the article focuses on one area, i.e., vocabulary learning strategies, the purposeful analysis of the vocabulary learning task, the planning, deployment, monitoring, and evaluation of learning behaviors in order to acquire the vocabulary of a second language. This article aims to provide a digest of recent research on vocabulary acquisition and to pinpoint areas that need further exploration. Recent volumes, especially the CUP volumes, that shed significant light upon different aspects of vocabulary acquisition include Huckin, Haynes, and Coady (1993), Harley (1995), Hatch and Brown (1995), Coady and Huckin (1997), Schmitt and McCarthy (1997), Atkins (1998), Wesche and Paribakht (1999), Read (2000), Schmitt (2000), and Nation (2001). We have seen a number of classic volumes on theories (e.g., Carter, 1987 Carter & McCarthy, 1988 McCarthy, 1990 Nation, 1990), research (e.g., Arnaud & Bejoint, 1992 Gass, 1987 Meara, 1989 Nation & Carter, 1989), and practical tips (e.g., Gairns & Redman, 1986 McCarthy & O'Dell, 1994). In fact, the vocabulary field has been especially productive in the last two decades. Numerous studies have been conducted comparing the retention effects of different vocabulary presentation strategies. Psychologists, linguists, and language teachers have been interested in vocabulary learning strategies for a long time (Levenston, 1979). The paper ends by calling for a diversification of effort in both top-down theory building that provides clearer guidance to future research and more bottom-up empirical research that goes beyond the presentation and retention of words. Instead of searching for the best strategies that produce the best results, the author argues that the choice, use, and effectiveness of vocabulary learning strategies depend on the task, the learner, and the learning context.

Specifically, the review focuses on task-dependent guessing strategies, dictionary strategies, note-taking strategies, rote rehearsal strategies, and encoding strategies. Next, empirical research along task, person, and contextual dimensions is reviewed. A tetrahedral model of person, task, context, and strategies is first proposed to foreground the review. This paper reviews empirical research on vocabulary learning strategies in a second/foreign language. Vocabulary Learning in a Second Language: Person, Task, Context and Strategies Peter Yongqi Gu Vocabulary Learning in a Second Language: Person, Task, Context and Strategies

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