The Role of Iranian EFL Learners’ Vocabulary Size in Vocabulary Use, Content, and Organization of Their Writing

Introduction: Previous inquiries in FL vocabulary knowledge targeted profoundly on the vocabulary pedagogical outcomes and writing improvement, however scant research has been done on the learners’ lexical competence in the writing process. In this spirit, the study endeavored to investigate the relationship between vocabulary size (VS) and vocabulary use, content, and organization in writing besides VS’s predictability in writing performance. Methodology: To this end, 30 intermediate EFL learners’ (15 males, 15 females) were administered on vocabulary size test (Nation, 2012) and Preliminary English Test (PET) of writing. The scores were analyzed and the results indicated significant positive relationships between VS and writing scores, and VS and vocabulary use scores. To investigate the predictability of VS in writing elements scores, regression analysis was applied. Results: The Linear regression revealed that VS variable accounts for 88.9% of vocabulary use in writing scores. The results proved the significant relationship between VS and writing on the one hand and VS and vocabulary used on the other hand. Conclusion: Based on the results, The study offers evidence that VS is a significant predictor in vocabulary use knowledge, which is vital for the and mastery of the required knowledge to be an effective writer.