VietTESOL International Convention 2026

Phrasal verbs (PVs) are a frequent yet notoriously difficult aspect of English vocabulary, occurring roughly once every 150–200 words in authentic discourse (Gardner & Davies,2007; Biber et al., 1999). Their idiomatic meanings, polysemy, and syntactic irregularities often hinder acquisition, particularly for learners in English as a Foreign Language (EFL) contexts. In Vietnam, the Global Success textbook series (Grades 10–12) provides a major source of input, yet little is known about how PVs are represented and how this aligns with learner knowledge. This study adopts a dual approach, combining a corpus-driven analysis of the Global Success series (74,370 words) with a diagnostic test of 43 high school learners. The corpus was examined for PV frequency, distribution, semantic transparency, and CEFR level, and results were benchmarked against the BNC2014 and PHaVE List. The diagnostic test, comprising 60 receptive and 60 productive items, was piloted and statistically validated (Cronbach’s α), enabling comparison between learner performance and textbook input. Findings show that the textbooks contain only 246 PV tokens (0.33% of the corpus), approximately half the density of authentic English. Coverage is uneven, with many PVs appearing only once and limited attention to polysemy. Learners performed better onhigh-frequency, transparent PVs recycled across grades but struggled with idiomatic or low-frequency items. Interestingly, several PVs absent from the textbooks were nonetheless known, reflecting extra-curricular exposure through media and online use.The study concludes that Global Success provides insufficient depth and recycling of PVs. Pedagogical implications highlight the need for systematic recycling, explicit treatment of polysemy, and supplementary materials to better support learners’ development of natural, idiomatic English.