Vocabulary in English for Specific Purposes and trades education in Mechanical Engineering: Insights from classroom talk and textbooks in Vietnam

<p><strong>This thesis investigates vocabulary in Mechanical Engineering (ME) in trades and ESP lessons in three colleges in Vietnam. In this context, students take an English for Specific Purposes (ESP) course with language teachers to develop English language skills and participate in theory and practice ME classes in Vietnamese. The overall aim of the study is to investigate the nature of vocabulary in written and spoken input through two studies. The focus of Study 1 was ESP lessons. I gathered ESP textbooks from three colleges in Vietnam (Leo, Libra and Taurus) and analysed their lexical features using Nation’s (2017) British National Corpus and Corpus of Contemporary American English (BNC/COCA) 25,000 word lists and the Fabrication Word List (FWL) (Coxhead et al., 2019). I also observed 247 minutes of the lessons of one ESP teacher in Leo College and identified vocabulary-related episodes (VREs) (Basturkmen & Shackleford, 2015). VREs are situations in class when teachers and students discuss vocabulary, question vocabulary use, or correct lexical errors. I then interviewed the ESP teachers from the three colleges to understand their rationales behind the development of learning materials and the use of vocabulary in class.</strong></p><p>Study 2 shifted the focus to spoken language in trades classes in Leo College. I observed 668 minutes of trades lessons with six teachers and had follow-up interviews with them and eight students in their classes to examine VREs and the use of vocabulary in this context.</p><p>Five key findings emerged from this research. First, classroom talk in Vietnamese in the trades lessons was challenging due to a large amount of technical vocabulary and meanings of the technical lexis. Several lexical items had specific meanings to the trades and the students had not encountered them before (e.g., bàn ren - die drill). Some words had technical meanings which were different from general Vietnamese (e.g., dao - cutter, the same word as knife in everyday language). These challenges are similar to findings in Coxhead et al. (2020a). Second, VREs were common in ESP and trades lessons, but the interaction level between teachers and students varied. The students initiated no VREs in their trades lessons, whereas they were more active in vocabulary discussions in the ESP lessons. Third, the VREs in the ESP lessons mostly targeted technical vocabulary and general lexis, while those in the trades classes only focused on technical terms. Fourth, the technical vocabulary in English in the ESP lessons showed little overlap with Vietnamese equivalents in the trades lessons, meaning students encountered different technical vocabulary in these courses. Finally, the ESP textbooks were lexically demanding for students in trades education with high vocabulary loads and a large number of technical words in the FWL (Coxhead et al., 2019), which suggests that this word list might be useful for the learners.</p><p>The thesis has several pedagogical implications. Suggestions include (1) encouraging collaboration between ESP and trades teachers on materials and content in Mechanical Engineering in preparation for the ESP course, (2) the addition of writing and speaking activities in ESP and trades classes to increase students’ vocabulary learning opportunities through language production, and (3) the simplification and clarification of lexis in ESP textbooks to aid students’ text understanding and acquisition of technical vocabulary in Mechanical Engineering.</p>