Lexical Bundles and Disciplinary Variation in Master Theses

Lexical bundles, as fixed-form recurrent word combinations of multiple words, constitute a significant portion of academic writing and play a pivotal role in producing fluent texts. Extant studies on lexical bundles have documented difficulties that second language learners, and particularly writers experience in producing these bundles in their academic writing. However, despite an extensive existing body of research on the use of lexical bundles in various fields, the use of such linguistic devices across various disciplines, particularly in the Iranian context is an under-researched area. Thus, this study examined the frequency, functions and structure of 4-word lexical bundle use in master theses of native English-speaking writers and Iranian second language (L2) writers across four different disciplines. For this purpose, two corpora, each containing 60 master theses, 120 theses in total, were selected and analyzed following a corpus-based approach. The findings of the study revealed that, overall, Iranian writers incorporated more lexical bundles in their texts than their native English counterparts and that their use varied functionally and structurally across not only native and nonnative corpora but also across disciplines. The study has important implications for Iranian L2 writers of the respective disciplines as well as genre-based instruction in English for both academic and specific purposes.