THE EFFECT OF CONCEPT SORT STRATEGY (CSS) ON IRANIAN PRE-INTERMEDIATE EFL LEARNERS’ VOCABULARY RECALL AND RETENTION

The purpose of this study was to explore the effects of concept sort strategy on Iranian English as foreign language (EFL) learners’ vocabulary recall and retention. For the purpose of this study, 90 pre-intermediate level participants studying in National Iranian Southfield Oil Company (NISOC) Language Training Centre in Ahvaz, Iran were selected non-randomly. They took part in a proficiency test and 60 of them were randomly assigned into two homogeneous groups. Then, both groups were given a pre-test before treatment to determine how well the subjects know the meaning of the vocabularies learned throughout the course. During an eleven-session course, both groups covered eight passages were extracted from New Headway, Pre-Intermediate developed by Soars and Soars (2009), Cristiano Ronaldo written by Taylor (2011) and Recycling by Border (1996). They were the materials taught by the researcher. The experimental group under treatment received concept sort strategy instructions while the control group received traditional vocabulary instructions. After each session, the research participants had to sit for an immediate post-test for the short term effect, recall, of the instructions. Finally, at the end of the course and after an interval of three weeks, the participants sat for their delayed post-test as an indicator of the long term effect, retention of the instructions. Paired Samples t-test was used to compare the means of the pre-test and the delayed post-test in both groups. The findings revealed that the vocabulary knowledge of both groups improved. However, Independent Samples t-test showed that there was not a significant difference between the two groups concerning vocabulary recall and retention. It was also revealed that the interval between immediate and delayed post-tests decreases the vocabulary achievement significantly in both groups.