Investigating the Effect of Inductive and Deductive Grammar Instruction and Input Enhancement on Iranian EFL Learners’ Grammar Achievement

The present study was conducted to investigate the effectiveness of deductive instruction of grammar with input enhancement and without using input enhancement. It also explored the effectiveness of inductive instruction of grammar with input enhancement and without input enhancement among Iranian EFL learners. The participants were female intermediate-level students who were studying English at Language Institutes. They were selected on the basis of administration of a pretest. Eighty intermediate students out of one-hundred and twenty were selected. They were divided into four groups of learners. Then five English tenses including simple present tense, present continuous tense, simple past tense, past continuous tense, present perfect tense were instructed to them during five sessions. The first group members were exposed to deductive teaching of grammatical structures and input enhancement techniques, such as color coding. The second group members were instructed the same materials without input enhancement techniques. The third group members were taught grammatical structures inductively using input enhancement techniques such as color coding during teaching. The participants of the fourth group were taught in the same way but without input enhancement techniques. To fulfill the purpose of the study, a grammar posttest was administrated to the participants to determine their performance on the use of five English Tenses. For analyzing the results, two independent Sample T-tests were used. Based on the mean differences, the results indicated that there was a significant difference between participants who were taught deductively with input enhancement and those who were instructed deductively without input enhancement. In addition, it was found that there is a significant difference between the student who were exposed to inductive teaching through input enhancement and those who were taught inductively without input enhancement. With respect to these findings, it can be concluded that the enhanced groups outperformed the other groups. Moreover, the results showed that input enhancement helped the participants to learn the structures better. Furthermore, inductive teaching of grammar proved to be more beneficial than deductive instruction.