Tracking the development in second language writers’ use of academic vocabulary in discipline-specific assignments

Few longitudinal studies have examined the development of second language (L2) writers’ use of academic vocabulary in discipline-specific assignments. This study tracked the use of expert vocabulary and proficient novice vocabulary in assignments written by 230 L2 writers across two semesters of postgraduate study in Education and Engineering programs. Gardner and Davies’s (2014) Academic Vocabulary List (AVL) and Malmström et al.’s (2018) Productive Academic Vocabulary List (PAVL) were used to represent each kind of academic vocabulary respectively. Linear mixed-effects model analyses found that Education students used significantly more AVL words in Semester 2 than in Semester 1, but no significant differences were found in the case of Engineering. This indicates that Education students tend to use more expert vocabulary as they progress further in their academic study, but Engineering students did not. Students’ use of proficient novice vocabulary does not appear to change across semesters in either discipline. Analysis of the writing of individual students largely supports the findings of the group analysis, but also revealed that lexical development patterns varied depending on individuals. Together these findings demonstrate the complex nature of vocabulary development.