This research examines vocabulary appearing in government-approved Japanese EFL senior high school textbooks by addressing the two research questions: (1) do Japanese EFL textbooks provide words that learners are more likely to meet in the real world? and (2) if Japanese students are able to master all of the vocabulary words taught in Japanese EFL textbooks, is that enough for them to be able to read authentic texts? To address these research questions, vocabulary in textbooks and the New General Service List (NGSL), which consists of 2,801 high-frequency words in general English, are compared to each other. Results show that textbooks are largely made up of the words in the NGSL at a level that is statistically significant; however, those that are covered by textbooks are only part of the NGSL. Overall, research findings indicate that indeed vocabulary items textbooks provide may be what learners frequently come across in the real world, but they cannot suffice in order for learners to read English texts intended for native speakers. Therefore, language teachers should ask students to read English texts extensively or watch English movies to widen their vocabulary size.
Shusaku Nakayama, Meiji Gakuin University, Japan