Improving vocabulary repertoire of second/foreign language learners has always been a concern for EFL teachers and learners due to its important role in language improvement. The depth and breadth of vocabulary are considered as the main criteria for determining learners' vocabulary knowledge. This study was an attempt to compare the effects of three vocabulary teaching techniques, i.e. anchoring, grouping and recalling on Iranian EFL learners' vocabulary depth and breadth. To this end, 60 learners were chosen to take part in this study who were then divided into three groups, each being exposed to one of the vocabulary teaching techniques, i.e. anchoring, grouping and recalling. In the anchoring group, they came up with associations for words that linked them together. In the grouping group, they sorted words into groups and categories. In the recalling group, they tried to remember a list of words and make notes about the ones they could not remember. The study used a pretest-posttest design and the learners were tested twice for their vocabulary depth and breadth both before and after the treatment phase. Results of the one-way ANOVA showed that the learners in the 'anchoring' group outperformed the other two groups in vocabulary depth. However, those in the 'grouping' technique performed better than the other two groups in their vocabulary breadth. The pedagogical implications of the findings are also presented for language teachers and institutes.
