INVESTIGATING GRAMMATICAL PROBLEMS FACED BY THE SEVENTH SEMESTER STUDENTS OF STKIP ABDI PENDIDIKAN PAYAKUMBUH IN WRITING INTRODUCTION CHAPTER OF RESEARCH PROPOSAL. EJPBI [Internet]. 2 Juni 2022 [dikutip 31 Juli 2026];11(1):16-30. Tersedia pada: https://journal.unismuh.ac.id/index.php/exposure/article/view/7121