The association between vocabulary knowledge and reading comprehension has been extensively researched. However, modeling the contribution of vocabulary knowledge within different frequency ranges to second language (L2) learners’ reading comprehension is an underexplored area. Thus, the present study examines the degree to which high-, mid-, and low-frequency-based levels of orthographic vocabulary knowledge are able to predict L2 reading comprehension. A vocabulary size test and the reading section of International English Language Testing System (IELTS) were administered to 256 tertiary-level Arab learners of English. The participants’ language proficiency ranged from B2 to C1 of Common European Framework of Reference (CEFR) levels. Results showed that high- and mid-frequency word ranges contributed uniquely to the L2 reading comprehension for the entire cohort. When the participants were categorized to relatively low- and relatively high-proficiency subgroups, only high-frequency range explained variance in L2 reading comprehension for the low-proficiency subgroup. Among the high-proficiency subgroup, high-, mid-, and low-frequency-based ranges offered unique contribution to L2 reading comprehension, but mid-frequency range explained the largest variance. The findings provide evidence aimed at informing approaches to the development of overall vocabulary size and the mid-frequency words, and not just a focus on the most frequent vocabulary, for the purpose of supporting L2 reading comprehension.

Listening comprehension constitutes a considerable challenge for second language learners, but little is known about the relative contribution of individual differences in distinct factors to listening comprehension. Since research in this area is relatively limited in comparison to that focusing on the relationship between reading comprehension and factors such as vocabulary knowledge and working memory, there is a need for studies that seek to fill the gap in our knowledge about the specific contribution of aural vocabulary knowledge, written vocabulary knowledge and working memory capacity to explaining listening comprehension. Among 130 non-native speakers of English, the present study examines what proportion of the variance in listening comprehension is explained by aural vocabulary knowledge, written vocabulary knowledge, and working memory capacity. The results show that aural vocabulary knowledge is the strongest predictor of listening comprehension, followed by working memory capacity, while written vocabulary knowledge contributes only marginally. The study discusses implications for the explanatory power of aural vocabulary knowledge and working memory to listening comprehension and pedagogical practice in second language classrooms.

The relationship between second language (L2) learners’ orthographic vocabulary knowledge and extensive reading is quite well researched. However, the way phonological vocabulary knowledge and extensive listening/viewing interacts remains not so well investigated. The current study examines the effect of extensive viewing of English movies supplemented by first language (L1) subtitles on aural vocabulary knowledge and listening comprehension among 78 tertiary-level Arab learners of English as a foreign language (EFL). The purpose of using L1 subtitles in this study was to enhance understanding of the spoken input through the L2 sound and L1 meaning mapping. Results of the study showed that the participants, after 5 weeks of extensive viewing, significantly improved their aural vocabulary knowledge and listening comprehension. The results indicated that aural vocabulary gain from extensive viewing was about 4.8 words per contact hour compared to 2.5 words from normal classroom input. The results also showed that prior vocabulary knowledge was strongly associated with vocabulary gain in aural modality.

It is uncontroversial to suggest that in order to be successful in academic study through the medium of English as a Foreign Lanuage, a learner will need a large general vocabulary and knowledge of...