مشخصات پژوهش

This study investigated the impact of encouraging discourse by English teachers on speaking performance and behavioral engagement among Iranian high school EFL learners. A quasi-experimental repeated-measures pretest–posttest design was employed with 50 female participants, aged 15, with 20 in the control group and 30 in the experimental group. Data were analyzed using linear mixed-effects models for speaking performance and classroom observation, and cumulative link mixed-effects regression for self-reported perceived behavioral engagement. Results revealed significant improvements in the experimental group's speaking performance particularly in fluency, coherence, grammatical range, and pronunciation, while the control group declined. For behavioral engagement, the experimental group exhibited improvements during the final sessions of treatment specifically in students' concentration, participation and persistence within classroom, rejecting null hypotheses for both research questions. Findings underscore encouraging discourse as a facilitative tool for enhancing communicative competence and engagement in EFL contexts.