Lexical and grammatical collocations in beginning and intermediate L2 argumentative essays: a bigram study

Collocations play an important role in L2 learners' fluent and idiomatic language production. Previous studies using a frequency-based approach to studying collocations underscored the potential to use association measures for distinguishing L2 writing proficiency. However, studies in this line have largely neglected the syntactic relation of words within a collocation. In addition, most L2 collocation studies have focused on learners at upper-intermediate levels and above, leaving the use of collocations by beginner-level learners understudied. Using the Yonsei English Language Corpus, this study investigated frequency (measured by normalized frequency and normalized deviance of proportions), formulaicity (measured by mutual information and t-scores), and diversity (measured by normalized entropy scores) of seven lexical collocations and four grammatical collocations in argumentative essays from beginning to upper-intermediate levels. Results showed that upper-intermediate L2 learners used more collocations with higher association strength and diversity than did beginning-level learners. In addition, collocations used by upper-intermediate learners were more idiomatic and suitable for L2 academic writing. The findings indicated that specific collocational patterns (i.e. adverb-verb and verb-preposition) could serve as reliable indicators of distinguishing beginning L2 writing from upper-intermediate L2 writing.