Lexical Bundles and Disciplinary Variation in Master Theses: The Case of Native versus Non-native Corpora

Writing academically as a formal skill is an essential requirement that graduate students are expected to acquire; however, the mastery of academic writing skill, especially in EFL contexts, is not an easy task for the graduate students. To be able to write effectively in English, the graduate students are required to acquire the academic discourse of their field of study which is usually a distinct genre with its own special discoursal and linguistic elements. Lexical bundles, as a certain linguistic structure, have been reported to constitute a large percentage of written academic text. Several studies have found that learners experience difficulties while using bundles by misusing, overusing or underusing these bundles in their writing (Adel & Erman, 2012; Hyland, 2008b; Wei & Lei, 2011). Nevertheless, although extensive studies have been done on the use of lexical bundles in various fields, there is still paucity of research into the use of lexical bundles across various disciplines especially in the Iranian context. Therefore, by adopting a corpus-based analysis approach, this study aimed to explore the frequency, structure and functions of lexical bundles across four different fields of study (business and tourism as soft sciences, and mechanical engineering and civil engineering as hard sciences) used by native English speakers and Iranian EFL master students. For this purpose, 120 theses from two corpora of master theses were selected. The first corpus contained 60 theses written in English by Iranian graduate students who studied at Eastern Mediterranean University (EMU), Famagusta, North Cyprus, and the other corpus included 60 theses written by native writers of English at three American universities: California State University, Iowa State University and University of Nevada. The findings of the study revealed that in soft sciences (business and tourism) and in one of the hard sciences (mechanical engineering), Iranian writers used more lexical bundles than their native English counterparts. Moreover, structural and functional differences were reported in each sub-corpus. This study can have several implications for writers of different disciplines to become familiar with different conventions and norms governing different fields of study. Keywords: lexical bundles, corpus, academic writing, master theses, Iranian EFL learners, native English writers