Sumalee P, Sukying A. The Effects of Derivational Suffix Instruction on English Vocabulary Knowledge in Thai High School Learners. rEFLections [internet]. 2024 May 3 [cited 2025 Apr. 17];31(2):335-52. available from: https://so05.tci-thaijo.org/index.php/reflections/article/view/272906