Salient language features in explanation texts that students encounter in secondary school chemistry textbooks

This study examines language features that students are likely to encounter in chemistry textbooks in EMI classrooms. In consultation with teachers, the presentation of science knowledge was examined in three chemistry textbooks commonly used in Hong Kong secondary English Medium Instruction (EMI) classrooms. Student textbooks were collected from eight Grade 10-12 chemistry classrooms. Adopting a functional linguistic approach (e.g., Veel's (1997) framework of text taxonomy), analyses showed that explanation is the most common text type in the three chemistry textbooks, and the five subtypes of explanations represented in the textbooks are causal (40%), factorial (24%), sequential (15%), consequential (13%) and theoretical (8%). The distribution of these different types of explanation texts and their features were examined to reveal the kind of language that students in EMI classrooms are likely to encounter when learning chemistry. The results show that explanation texts served as a primary linguistic reservoir for EMI students to learn the language of science. The analysis of the language features of these texts could be used to inform future pedagogies aiming at making these textbooks more accessible to students learning in English and facilitating both their science learning and control of scientific English. (c) 2019 Elsevier Ltd. All rights reserved.