English Idiom Use Development in Thai EFL Writers

Abstract

This article reports the findings of a 3-year longitudinal study on the development of English idiomatic expression usage. The study aimed to examine the use of English idiomatic expressions in 464 essays written by 58 students from a university in Thailand. The researcher tracked these learners from the second semester of the 2022 academic year to the first semester of the 2024 academic year. Data from the essays were analyzed using content analysis to identify six types of idiomatic expressions employed by the learners in each essay. The findings revealed a total of 771 idiomatic expressions used. After removing duplicates, 523 unique expressions remained. The most frequently used type was transparent idioms, followed by semi-transparent idioms, while the least used type was proverbs, with only four instances. The results indicate that the learners increased their use of English idioms over the three-year study period. However, this increase was only in quantity, not in quality.