摘要：This paper investigates the implementation of bilingual based instruction in teaching English for Academic purposes at Islamic University. It was investigated by using case study with single case study at Indonesian Islamic University. The findings showed that the lecturer used English and Indonesian as a language interaction. The functions of Indonesian used by the lecturer were to translate, clarify, explain, lexical gap, address specification, and address affection. The lecturer sometimes alternated her language unconsciously. Lecturer’s language functions not only as language instruction but also as language source. This bilingual based instruction facilitated more exposure to the students; therefore the students can imitate lecturer’s language, then they can practice the language, finally, they can acquire the language.
关键词：Bilingual-based Instruction; English for academic purposes; Islamic University
