Focusing on metadiscourse markers during EFL writing classes has garnered research attention, yet few studies were conducted on online expository writing. This study explores the effect of metadiscourse markers instruction on expository writing of 80 male and female EFL learners in the school context, selected through convenience sampling and an interview followed with a smaller number of participants. Initially, the eighty participants were assigned to experimental (n=40) and control (n=40) groups after checking homogeneity in terms of English proficiency level. The participants in the experimental group received explicit instruction of markers, whereas the control group received the conventional curriculum-based writing instruction that included similar material/topics, except for the explicit focus on metadiscourse markers, all through a uniform digital platform mandated in the state-run schools. The frequency/use of metadiscourse markers in the writing assignments of the participants per session and the total was noted, and then a corpus of 80 collected essays was analyzed by a trained rater and researcher to both analyze whether metadiscourse markers instruction had any significant effect on expository writings and to determine which metadiscourse markers showed up in the texts written by students more. Finally, a semi-structured interview was conducted with eight EFL instructors to explore their attitudes. Statistical test of Analysis of Covariance showed a significant effect of metadiscourse markers instruction on EFL learners’ expository writing. Another finding was that participants employed interactional metadiscourse markers frequently. Implications for policy-makers, students, and teachers indicate that free access to online writing resources improves learning perceptions/outcomes. Manuscript profile

Persuasive writing is considered a complex genre for EFL learners to master and yet vital for academic arguments. As metadiscourse markers are recognizable and familiar devices to persuade, the purpose of this study was to investigate the effects of their explicit online instruction on Iranian EFL learners' persuasive writing. The participants were homogenous EFL learners at the intermediate level, divided into two groups: experimental (n=40) and control (n=40). An official e-platform used in Iranian state-run schools was used for online instruction. According to a regular schedule, the participants received different passages containing metadiscourse markers. The teacher assigned the experimental group to notice and discuss the markers in small groups. Then, a passage-related topic was assigned and the learners wrote a persuasive essay in each session. For the control group, the same procedure was adopted except for the explicit focus on metadiscourse markers. Finally, a writing test demonstrated the significant effect of explicit instruction on persuasive writing of EFL learners, through statistical analysis explaining participants’ attitude and high frequency of - interactive type markers. Learners’ attitudes were also examined through interviews. Pedagogical implications are suggested to include explicit focus on metadiscourse markers in writing courses. Manuscript profile