The effect of vocabulary size in oral productions on the speaking proficiency of EFL learners

Abstract

This s tudy inves tiga tes the effect of using a bigger vocabulary size in oral class room presenta tions on the speaking profi ciency of students in English as a foreign language . The s tudy was conducted with 30 freshman s tudents doing their lis tening andspeaking course in Semnan Uni versi ty. For the enti re course of 12 weeks , the s tudents in the experimental group were asked to present their productions in terms of the vocabulary they employed, whi ch was also the focus of the teacher’s evalua tionin each session. At the end of the course , they were interviewed for their profi ciency in speaking. The descripti ve andinferential calculations were done based on a modi fied version of an oral profi ciency i nterview scale sugges ted by Penny Ur. The answers were recorded and their fluency and accuracy were graded. The resul ts sugges t tha t s tudents wi th a vocabularyrich producti on improved their speaking profi ciency in English more than other students did.Keywords: Vocabulary size , speaking profi ciency, production, fl uency, accuracy, interview.