The role of context in the word family debate

There has been debate regarding how to define the lexical unit for the receptive skills, with different levels of inclusiveness being possible depending on learner proficiency and pedagogical or research purpose. The most frequently-used definitions for L2 reading are the lemma, flemma, and Bauer and Nation's (1993) level-6 word family (WF6). When WF6 is used, it is assumed that if one family member is known, unfamiliar members can be understood when encountered in meaningful contexts. Past investigations of this assumption have been criticized for assessing knowledge of morphologically-related words only in isolation or in sentence-length contexts. The present study addressed this concern by examining Japanese university students' ability to understand related words in isolation, in limited-context sentences, and in page-length passages. The relationship between baseword and derivational form knowledge was weak, and the level of contextualization had little effect on this relationship. These findings corroborate past findings and support the use of limited-context assessment in research on the word family and the relationship between vocabulary and reading.