A Comparison of the Effects of Explicit and Implicit Use of Instructional Techniques (Glossing, Semantic Mapping, and Imagery) on L2 Vocabulary Comprehension and Production

This paper is a report on a study which compared the impacts of explicit and implicit uses of three techniques of vocabulary presentation (i.e., glossing, semantic mapping, and imagery) on the vocabulary comprehension and production of 175 Iranian EFL learners. The participants were all intermediate learners at Marefat Language Institute in Qazvin, Iran. A pretest was given to the learners to make sure they had no prior knowledge of the target words. As a result, the words which the participants already knew were excluded from instruction. After the pretest, the participants were assigned to six groups. Half of the groups were taught explicitly, and the other three received implicit instruction. Each of the six groups received instruction (either explicit or implicit) for a whole semester through one of the three vocabulary teaching methods. Knowledge of receptive vocabulary was measured through a multiple-choice test, and vocabulary production was assessed via a fill-inthe- blank test. After the data were collected, two separate t-tests were used for statistical analysis. The results showed explicit instruction of all the three techniques at issue to be more effective than implicit presentation in improving both vocabulary comprehension and production.