The relationship between Iranian EFL learners` vocabulary command and the extensive reading materials they choose

In order for foreign language learners to comprehend English passages, it entails possessing a good command of vocabulary knowledge. The present study aims to investigate the vocabulary size of Iranian EFL learners at intermediate level and to examine whether EFL learners’ vocabulary size affects their selection of books in terms of graded readers or authentic books. A test of vocabulary size was administered to 41 EFL learners participating in reading classes of Khuzestan Jahad University before implementation of extensive reading as a supplemental activity in a basic reading class and a questionnaire was given after their participation in the Extensive Reading for three months. The results indicate that the participants with a larger vocabulary size indeed prefer authentic books to graded readers. However, the findings also reveal that EFL learners’ vocabulary size might not be a crucial factor for their choosing ER materials and those with poor performance on the test of vocabulary size chose authentic books as well. This suggests that EFL adult learners might need authentic books instead of graded readers while implementing ER in reading classes.