A multi-word unit approach to general academic vocabulary
Pre-university, undergraduate and postgraduate vocabulary
Some examples of corpus-based, multi-word unit research in general academic vocabulary have already been discussed in Chapter 4, including Biber (2006), Ackermann and Chen’s (2013) ACL, Durrant’s (2009) research into collocation in academic texts, and Simpson-Vlach and Ellis’s (2010) Academic Formulas List. Liu’s (2012) study investigated a range of multiword units in academic corpora, drawing on some of earlier research to find out more about lexical bundles, idioms and phrasal verbs for general academic purposes. Liu used the academic sections of the COCA (nearly 83 million running words) and BNC (over 15 million running words) for the 2012 study. He interrogated these corpora using existing lists of general academic lexical bundles (Biber et al., 1999; Carter & McCarthy, 2006; Simpson-Vlach & Ellis, 2010; phrasal verbs (Biber et al., 1999; Gardner & Davies, 2007); several of his own earlier studies, and idioms sourced from a number of dictionaries. Biber et al.’s (2004) categorisation system was used to qualitatively identify the functions of the lexical bundles (discourse organising bundles, referential bundles and stance bundles — see Chapter 4 for more on this method). Liu (2012) also provided three frequency-based bands of 228 frequent multi-word constructions: the first band contains items which occurred more than 100 times in the corpora (77 constructions), the second band contains 85 constructions which occurred 50—99 times and the third band contains 67 items that occurred 20—49 times. Here are examples from the most frequent band: Such as (det + N), as well as (det + N), NP suggest that, according to (det + N) and (be) based on (det + N). These examples show again the prevalence of high frequency vocabulary in academic texts and that high frequency words often make up high frequency multi-word units.