An investigation of morphological awareness in Japanese learners of English

Developing morphological awareness (MA) is an essential component of vocabulary growth, given that it can contribute to enhanced depth of vocabulary knowledge and provides a pathway to deeper associations with more members of a word family. Despite the considerable body of vocabulary research, specific relationships between different aspects of MA are not yet well understood. This is particularly the case for learners of a second language, such as Japanese ESL (English as a second language) learners (JESLLs). This paper reports on a study which focused on aspects of MA, using a word segmentation task and an affix elicitation task. The JESLLs were more adept at morphological segmentation than a comparison group of native speakers of English (NSs), a finding which highlights the influence of instruction in developing MA. Performance on the morphological tasks was analysed using Bauer and Nation's list of different levels of English affixes, to examine potential effects of morphological variables (frequency of affixes, productivity and semantic transparency). Semantic transparency was influential in the participants' performance on the word segmentation task. These variables, however, did not account for performance on the affix elicitation task. When vocabulary size (VS) was taken into account, productive MA was positively related to both receptive and productive VS for the JESLLs. Among the NSs, it was, in contrast, receptive MA that correlated with both types of VS. These findings are discussed in terms of the nature of depth of L2 vocabulary knowledge (relative to that of L1), in relation to MA.