2026. The Impact of Project-Based Learning on Vocabulary Retention among Grade 5 Learners: A Study at Ngo Thoi Nhiem Primary School, Ho Chi Minh City. The International Journal of Language Studies (ISSN : 3078 - 2244). 3, 2 (Jun. 2026), 180–198. DOI:https://doi.org/10.60087/ijls.vol3.n2.011.