Long term effect of keyword and pictorial vocabulary teaching methods on Iranian EFL learners’ vocabulary development

Abstract This study intended to examine the effect of two mnemonic methods of vocabulary teaching i.e., key-word and pictorial method on the Iranian EFL learners’ immediate and long-term retrieval of vocabulary. For this purpose, 90 intermediate EFL learners were selected from among all 110 eleventh-grade students studying in a senior high school in Shahriyar, based on purposive sampling. Then, they were distributed in three groups (two experimental and one comparison group). In the first experimental group, the students were taught vocabulary through key-word method and in the second one, they were taught adopting pictorial method. Further, the third group of students was assigned as comparison group for which the vocabularies were presented using traditional methods such as mere translation. The first three 1000 most frequent words from Nation and Beglar’s (2012) test of vocabulary size were used as pre-test, post-test and two separate delayed post-tests with a two-week interval. The obtained results from a repeated-measure ANCOVA suggested that adopting both keyword and pictorial methods of vocabulary teaching can exert great influence on the development of EFL learners’ vocabulary knowledge. However, using pictorial method can lead to achievement of better outcomes in vocabulary compared to employing keyword method. In addition, it was found that teaching foreign language vocabulary through pictorial and keyword methods has long-term t effect on the EFL students’ vocabulary. Keywords: EFL learners, vocabulary learning, retrieval, mnemonic, keyword, pictorial