A Study on the Different Dimensions of an EFL Learner's Vocabulary Knowledge

The purpose of the present study is to investigate the relations of Korean EFL learners' different dimensions of vocabulary knowledge, in terms of word frequency levels and language proficiency. Ninety-one EFL university students in Korea participated in the study, and a total of 25 vocabulary tests, ranging from 1,000 to 8,000 word frequency levels in both receptive and productive forms, were administered throughout one semester. The lexical Frequency Profile and P-Lex program were adopted to measure participants' free vocabulary knowledge, along with an official TOEIC test as a measure of language proficiency. The results have shown that in general, 1) a participant's receptive (R), controlled productive (CP), and free productive (FP) vocabulary knowledge significantly decreased as word frequencies decreased, 2) the gap between a participant's R and CP vocabulary was higher for high frequent words and lower for less frequent words, 3) R and CP vocabulary had a strong correlation to language proficiency, and 4) FP vocabulary had no correlation to any of R, CP, and TOEIC scores. Implications and limitations of the current study are discussed.