Metacognitive knowledge, vocabulary size and EFL reading comprehension of Chinese tertiary students

The present study sets out to investigate how Chinese tertiary EFL readers utilize metacognitive knowledge in their academic reading process, to discover the possible differences between less successful readers and successful readers in utilizing metacognitive knowledge in their reading and to map out the relationships among metacognitive knowledge, vocabulary size and EFL reading comprehension ability.;The study consists of two phases. Five less successful and five successful Chinese tertiary EFL readers participated in the think-aloud reading task and the interviews in Phase One study. Twenty-nine types of metacognitive knowledge were identified and categorized into nine subcategories under two major categories of person knowledge and strategy knowledge following Flavell's metacognitive framework (1979). Less successful readers used more frequently most types of metacognitive knowledge than their successful counterparts. Vocabulary was found to be the major obstacle hindering the students' reading progress for both groups of students. However, successful readers deployed strategy knowledge more flexibly to address the vocabulary gap than less successful readers. Differences were also discovered on the motivational and affective characteristics such as reader role, goal of reading, interest and self-efficacy between the two groups. Successful readers were more actively engaged in reading and provided interpretations of the text on their own authority. They also demonstrated an accurate self-knowledge and higher levels of task-mastery goal and interest toward reading.;Phase Two study consists of 548 non-English major sophomore students in a large-scale survey on the relationships among metacognitive knowledge, vocabulary size and EFL reading comprehension ability. The instruments include Questionnaire on the Metacognitive Knowledge of EFL reading comprehension, Vocabulary Levels Test (Nation, 1990) and EFL Reading Comprehension Test. The findings reveal that Chinese tertiary EFL readers have a good command of 2,000-word level and approach 3,000-word level. Vocabulary size does not only exert direct influences on EFL reading comprehension ability, but also plays a significant moderating role in regulating the effect of metacognitive knowledge on EFL reading comprehension ability. When the vocabulary size reaches above the threshold of 3,000 words, metacognitive knowledge plays an increasing role in EFL reading comprehension ability.;The theoretical, empirical and educational contributions of these findings for L2 reading are discussed, as are suggestions for future research.