The Acquisition Order of Vocabulary Knowledge Aspects in Thai EFL Learners

The present study explored vocabulary knowledge as a multi-aspect construct by examining the acquisition order of different vocabulary aspects and the relationships between these aspects. A battery test of receptive and productive vocabulary aspects, based on Nation’s (2013) framework, was administered to 156 Thai EFL learners in tenth (n = 84) and twelfth (n = 72) grades. Two different grades of Thai EFL learners were used to better describe the vocabulary acquisition process. The results indicated that scores on the tests assessing receptive knowledge of an aspect were higher than scores on the productive knowledge tests, for both grades. However, overall, the twelfth-grade learners performed better than the tenth-grade learners. The findings also revealed significant correlations between knowledge of the different aspects. Furthermore, the Implicational Scaling (IS) analysis revealed that the two grades had distinct implicational patterns of vocabulary aspects. These results provide empirical evidence for the vocabulary acquisition pattern. The results also suggest that vocabulary knowledge is an incremental learning process and that exposure to vocabulary knowledge has positive effects on vocabulary acquisition.