Abstract
Since Halliday's expounding on Theme, this concept has aroused certain research attention, both theoretical and empirical. Its connotations and functions have been elaborated and Theme choice has been compared across genres, disciplines and writers of different English proficiency levels. However, the limited data in existing studies led to some conflicting conclusions and interpretation in Theme use is relatively inadequate. A thorough understanding of Theme in academic writing is therefore expected before it could be incorporated successfully into writing instruction.