The more the merrier? Bilingualism in an academic perspective: Exploring the implementation of English-medium instruction in Taiwanese tertiary education

The purpose of this study was to investigate the effects of English-medium instruction in the context of Taiwanese tertiary EFL and content area education. Due to the prevalence of globalization, English has gradually become the only language of instruction in academia, especially in Asia such as Taiwan. It is thus believed that this English only policy would greatly benefit students' L2 development as well as content knowledge acquisition. However, this article claims that English-medium instruction could be ineffective and even frustrating for students without professional teacher training programs. There were 104 students participated in this study at a university in northern Taiwan. The data were collected from participants taking the course for 18 weeks, including students' Pre-questionnaires and an institutional listening & speaking test at the beginning, and Post-questionnaires, a semistructured interview together with a final institutional listening & speaking test at the end. The results indicated that students perceived and experienced the English-medium EFL and content area instruction differently with various learning outcomes and attitudes. Also, instructors were found to be of great importance to students' learning results without any exception. Overall, this study not only provides empirical evidence that English-medium instruction is not always effective for ESL/EFL students without proper teacher training programs, but also sheds light on what policy makers and language teachers need to consider for creating a more effective and student-friendly English learning environment.