Which Words Should and Do the Students Know at Each Proficiency Level?

Due to the extensive research that they have done on word lists and word frequency, applied linguists and publishers are an important source of information regarding which words students ought to know and should be taught (Youngblood & Folse, 2017). One early list is West’s (1953) general service list, and most scholars since West (1953) agree that knowledge of the 2000 most frequent words in English constitutes a vital base on which to build up more sophisticated lexical knowledge. Some frequencies of a word remain relatively stable over time, for example, articles in English tend not to change in frequency, and, unsurprisingly, the is the most frequent word in both expert user English and learner English corpora. However, with changes in technology and other aspects of life, frequencies and meanings of some words evolve over time. Browne, Cul-ligan, and Philips (2013) report on the New General Service List (NGSL, www.newgeneralservicelist.org/), which takes account of changes in frequency since West’s (1953) original list was developed. They propose a new core of 2800 words, including 700 for spoken English. The website that Browne and colleagues have developed is based on a very large corpus of 273 million words and also provides smaller sublists relevant to different genres, including Business (1700 words) and Academic English (960 words). Word lists are often grouped into ‘bands’ of 1000 words, so that the ‘1000’ frequency band is a list of the 1000 most frequent words, the ‘2000’ band the next most frequent, and so on.

Nation (2001, p. 17) provided a good idea of the coverage of the most frequent 1000 and 2000 words in English, in Table 4.1.

Table 4.1 shows that in conversation, the 1000 and 2000 frequency bands in English account for 90.3% of the vocabulary used (84.3% 1000

Table 4.1 Coverage of the Most Frequent Words in Various Genres

frequency band + 6% 2000 frequency band). Even in academic texts, 78.1% of the words come from the most frequent 2000 words. However, Nation estimates that a learner needs to know about 98% of words in a text for ‘guessing from context’ to work efficiently in comprehension. Thus, beyond the most frequent 2000 and the academic word lists (AWLs) of Coxhead (2000) and Gardner and Davies (2014), learners in an IEP who are preparing to study other subjects in English also need to focus on the ‘Other’ 13.3% for academic texts.

The base of words in the productive lexicon of each learner in the IEP is one important factor. It would not be economical to list all the frequent words used by students in a book. The reason for this is that (a) there is immense overlap in the most frequent 2000 lemmas per level; (b) the online lists allow us to efficiently provide lists by level and by LI that go as far as the 3000-9000 level that could be most useful for teachers and programs. Thus, the frequency lists of each level with combined Lis and for each language by level are provided online at: https://github.com/ELI-Data-Mining-Group/Pitt-ELI-Corpus, or by contacting the author. They are available in spreadsheet format. Each word is ranked for frequency, e.g., ‘the’ is the most frequent word for most intermediate learners and is ranked ‘1’ in the list. In addition to raw frequencies in the texts, they are also listed with estimated frequencies per million words so that frequencies from level to level can be more easily compared. Curriculum planners might use these lists to develop their own lists for instructional intervention based on which words students may not be using enough. In Chapter 5, further suggestions are made about which verbs might receive more instructional intervention. Obviously, the most frequent words in English texts are function words, for example, the, or, and, and but, and then frequent lexical items for daily life such as have, go, friend, and job. This frequency is reflected in the learner data, but there are some differences between learner frequency lists and native speaker lists. For example, the word visa does not appear at all on www.wordfrequency.info and is listed as a 5000-level BNC-COCA-25 word at https://lextutor.ca/. However, it is ranked approximately 1000 in frequency for the Level 3 IEP students: obviously, an international student needs a ‘visa’ to be a student in the United States, and therefore they know and use this word. Students thus use some words more frequently than expert speakers do, and they know those words earlier in their acquisition trajectory than expert native speaker frequency lists might suggest. We will see that this second language-specific lexical knowledge has implications for measuring vocabulary growth in an IEP.