Analyzing lexical characteristics in IELTS Writing Task 2 essays: A study of Vietnamese students from non-English majors

This quantitative study examines the lexical features of IELTS Academic Writing Task 2 (IAWT2) essays written by Vietnamese non-English-major undergraduates, focusing on following writing prompts (WP): WP1 (encouraging bicycle use), WP2 (urban living and health), and WP3 (preferences for homecooked versus fast food).A corpus of 479 essays was analyzed to explore the relationships between lexical diversity, content word types, and the use of academic and less common vocabulary.Results reveal that nouns and adjectives significantly enhance lexical diversity, while verbs and adverbs contribute minimally.Academic vocabulary coverage varied, with WP1 demonstrating the highest proportion, while WP3 relied more heavily on high-frequency vocabulary.Lexical diversity was most pronounced in WP2 and WP1, with WP3 essays showing less variation in content words.These results underscore the need for task-specific lexical training to improve students' academic writing proficiency and vocabulary use in IAWT2.