Effects of Prefix Availability and Vocabulary Size on Japanese EFL Lexical Inferencing

Abstract

　　The present study examined the effects of (a) a prefix clue in an unknown word and (b) the relationship between the use of prefixes and L2 vocabulary size on EFL learners’ lexical inferencing in reading. Previous studies have shown that L2 learners make use of morphological clues in unknown words to infer word meaning. In addition, some studies have demonstrated that the use of morphological clues contributes to L2 learners’ vocabulary knowledge through lexical inferencing ability. However, few studies have examined the relationship between the use of morphological clues and its contribution to lexical inferencing. In an experiment, a total of 35 Japanese EFL undergraduate and graduate students inferred the meanings of 11 target words whose prefixes were available for participants and 11 words whose prefixes were unavailable. All target words were presented in sentences that were not sufficiently informative to be able to infer the word meaning. The prefix availability and sentences containing target words were examined and created through two pilot studies. The results showed that prefix availability contributed to lexical inferencing, but it was also found that the effect of prefix availability on lexical inferencing might not differ in respect of learners’ vocabulary size. Finally, the possible ways of applying the findings of the present study to teaching English in the context of EFL are discussed.