Corpus-Based Materials and Learning Non-Congruent Idioms by Iranian EFL Learners: Enhanced and Unenhanced Input

The current study aimed at probing the impact of using enhanced and unenhanced corpus-based material on non-congruent idiom learning by Iranian female intermediate EFL learners. Initially, via adopting a quasi-experimental design, 120 participants from an English institute in Sanandaj were chosen conveniently from among different classes. They were given a Nelson Proficiency Test, the results of which were used to select 90 participants based on the standard deviation and the mean of the scores. These participants were then divided into three groups each consisting of 30. Prior to the treatment, the participants were given a researcher-made non-congruent idiom test. As for the treatment, the first experimental group received enhanced corpus-based materials while the second experimental group received unenhanced corpus-based materials. The control group received no treatment in terms of enhanced and unenhanced corpus-based materials and followed the regular syllabus of the institute. At the end of the treatment, the same pretest of non-congruent idioms was administered to the participants in the three groups as the posttest. The results of ANCOVA indicated that both enhanced and unenhanced corpus-based instruction had significant effects on learning non-congruent idioms. However, there was a significant difference between the effects of unenhanced and enhanced corpus-based instruction on learning non-congruent idioms, in favor of the second. Based on the findings of the present study, EFL teachers are encouraged to employ corpus-based materials in teaching L2 in general and in particular when it comes to teaching non-congruent idioms.