This study investigated the effect of input- and output-based instruction on EFL Algerian learners’ grammar performance .The treatment conditions were implemented with thirty-eight young adult EFL learners in two intact classes from the English Department. The two groups were randomly assigned to one input-only group (n =19), and one input-plus-output group (n = 19). The input-only group was given comprehension practice only. The input-plus-output group was given both comprehension and production practice. A pretest/treatment/post-test design and comprehension and production tasks were used as both the pre- and post-tests. Descriptive statistics indicated that the second group outperformed the first group.However, the statistical analysis (Anova) revealed that the instructional effect did not amount to statistically significant learning gains.
Keywords: Input comprehension, Linguistic Forms, Output practice
