Abstract：Abstract: Based on Biber et al.’s (1999) structural framework and Hyland’s（2008）functional framework, the present study compared the structural types and functional categories of 4-word lexical bundles in two corpora of Mechanics journal articles written by English native writers and Chinese writers. The results showed that, structurally, journal articles of English native writers were characterized by phrasal bundles, while those of Chinese writers were characterized by clausal bundles. A comparison to the findings of the previous research indicated that the clausal feature was not unique to Chinese writers, but a common feature of inexperienced academic writers. Functionally, English native writers and Chinese writers do not differ much in the proportions of the functional distribution of bundle types and tokens. Additionally, the study showed that both types of writers employed bundles with different structural characteristics to serve similar discourse functions. Finally, the study discussed the implications of these findings for teaching second language academic writing.
