The results of this study confirmed that different personality behaviors have a significant impact on Iranian EFL learners’ vocabulary knowledge. It was also found that there is a significant difference between different personality traits regarding their vocabulary knowledge.This study found different results comparing to those of Omidi (2004). He investigated the relationship between Iranian EFL students’ assertiveness and their ability in argumentative speech and oral proficiency. A negative relationship was found between students’ assertiveness and their ability in argumentative speech. In addition a negative correlation was found between students’ assertiveness and their mastery of oral proficiency. Thus, the results of this study contradict the findings of Omidi (2004).
The results of this study also were in line with what Erton (2010) found. He measured the reflections of different personality types in students’ developing different learning styles for themselves. The results showed that there is not a statistically strong, but a low relationship between the personality traits of the learner, the way he/she establishes the learning styles and reflects these characteristics into success while learning a foreign language.The findings of this study confirmed the results of Fazeli’s (2012) study that found the significant influence of personality traits on the choice and use of memory English language learning strategies for learners of English as a foreign language, and the role of personality traits in the prediction of use of such Strategies. The results showed that there is a significant relationship between four traits of personality and the choice and use of memory English language learning strategies, but personality traits cannot be as a strong predictor with high percent of contribution to predict the choice and use of the memory English language learning strategies.The findings of this study also approved the findings of Behtarinezhad’s (2013) findings on the relationship between personality traits and EFL learners’ metadiscourse competence.
She found a significant relationship between these two variables.