The Impact of Code-Switching On Vocabulary Learning Among Iranian Upper-Intermediate EFL Learners

This study aimed to investigate the impact of code switching on Iranian upper-intermediate EFL learners' vocabulary learning. To this end, 64 participants out of 90 male students were selected and randomly divided into two equal experimental groups - experimental and control groups. Then, the groups were pretested by a vocabulary pre-test. Then after, the participants of experimental group received the treatment, i.e., using code switching. After the treatment ended, both groups took the post-test of vocabulary. The results of paired and independent samples t-tests revealed that the experimental group outperformed the control group on the post-test. The results showed that there was a significant difference between the performance of the experimental and the control group on the post-test