抄録
This paper employed the lexical coverage construct, defined as the percentage of words in a text that a reader understands (Laufer & Ravenhorst-Kalovski, 2010, p. 16), to establish a) the vocabulary size needed to achieve adequate comprehension of the TOEFL (ITP) reading section and reading passages taken from two EFL textbooks, and b) whether the EFL textbooks provide opportunities for vocabulary instruction sufficient to achieve specific reading comprehension targets; in this case, a reading comprehension level of approximately 50%-55% (at the intermediate level) and 65% (at the upper-intermediate level) on the TOEFL (ITP). Using the RANGE software package and employing 95% and 98% lexical coverages, the results pointed to a gap of at least 2,500-4,000 word families between TOEFL reading texts and the two EFL textbooks. At 98%, the gap was approximately 6,000 word families. It was concluded that the two textbooks do not provide sufficient vocabulary instruction for students to meet the lexical demands of the TOEFL reading comprehension targets. The implications of this for textbook selection and vocabulary instruction are discussed.
