AN INVESTIGATION INTO EFL MAJORS’ VOCABULARY KNOWLEDGE AND THE VOCABULARY COVERAGE OF AN EFL COURSEBOOK AT TERTIARY LEVEL IN VIETNAM

Abstract

The study sheds light on Vietnamese English-majored university students’ vocabulary knowledge with the use of Webb, Sasao and Ballance’s (2017) [1] Updated Vocabulary Level Test Form B. Also, the researchers analyzed the EFL textbook that was currently being used by those students regarding the vocabulary coverage of the book in relation to the two thresholds of 95% and 98%. To fulfill this objective, a frequency-based analysis of word families using the Vocabprofilers on the https:\\www.lextutor.ca\ website were conducted with the 68,918-word textbook corpus. The group of students was found to master only the first 1,000 word level, yet they achieved quite encouraging results with relatively small proportions of unknown words in the highest frequency word levels. Interestingly, the number of students mastering the lower frequency words of 4,000 and 5,000 word levels were found to be higher than that of the higher frequency words of 3,000 word level, which emphasizes the importance of teachers’ appropriate selection of vocabulary input for Vietnamese students to enhance their opportunities and exposure to the most frequent and dominant English words. This requirement seems to be fulfilled with the textbook being used for the very students - Real Life Upper Intermediate, which was found to effectively represent the highest-frequency words of the English language. Moreover, the textbook, which was estimated to require a receptive lexical knowledge of 3,000 and 4,000 word families for 95% and 98% coverage, is preliminarily evaluated as an appropriate selection for the students.