Vocabulary

Abstract

Acquiring vocabulary knowledge is a vital part of L2 learning because vocabulary plays a significant role in every mode of communication (reading, listening, writing, and speaking). For learners to become independent users of a L2, they must know many thousands of words and learn how to use them well in communication. For example, learners of English must acquire up to 9,000 words (e.g., happy) and their morphologically-related forms (e.g., happiness, unhappy, happily) to comprehend spoken and written texts (e.g., conversation, television programs, films, novels, and newspapers) (Nation, 2006; Webb & Rodgers, 2009a, 2009b). Moreover, acquisition of L2 vocabulary entails learning different aspects of word knowledge such as word parts, collocations, and associations, not only learning form-meaning connections. Thus, the teaching, learning, and researching of L2 vocabulary can be highly complex. The purpose of this chapter is to provide a guide to researching instructed second language vocabulary acquisition. The chapter sets out to provide (1) an overview of key concepts in vocabulary research, (2) a brief overview of L2 vocabulary research focusing on intervention studies, (3) an overview of a frequently employed study design (pretest-posttest design), different measures for assessing L2 vocabulary knowledge as well as options and cautions for interpreting data, (4) advice for future vocabulary researchers, and (5) tips to overcome potential challenges.