Longitudinal analysis of breadth of vocabulary knowledge in mediating metacognitive knowledge and reading in foreign language young learners

Metacognitive knowledge is essential to vocabulary learning and reading. However, there have been few longitudinal studies investigating how the breadth of vocabulary knowledge mediates the relationship between metacognitive knowledge and reading over time in a foreign language context. This study involved 361 primary school students, who were observed from third grade to fifth grade. They were given tests on metacognitive knowledge, breadth of vocabulary knowledge, and reading comprehension three times over three years. The metacognitive knowledge test assessed students’ understanding of cognitive activities. Vocabulary knowledge test focused on learners’ receptive vocabulary knowledge. Reading comprehension test focused on their ability to understand sentences and texts. A longitudinal mediation analysis was conducted to explore the mediating role of breadth of vocabulary knowledge in the relationship between metacognitive knowledge and reading. The results supported a significant and positive correlation among the variables studied. Additionally, the findings supported the mediating role of breadth of vocabulary knowledge in metacognitive knowledge and reading comprehension. Implications for developing metacognitive knowledge, vocabulary knowledge, and reading in young learners were discussed.