Thai English as a foreign language learners' difficulties in using context clues to understand unfamiliar words

The purpose of the study was (1) to investigate whether context clues can benefit Thai grade 12 high school EFL students in guessing the meanings of unfamiliar words, and (2) to investigate the students’ difficulties in using context clues to guess the meanings of unfamiliar words. The participants were 60 grade 12 students at Khokyangwittaya School, Surin province, in the first semester of the academic year 2014. The research instruments were handouts about context clues, vocabulary test, and two context clue tests: version 1 (without glossary in Thai) and version 2 (with glossary in Thai provided). The participants practiced the use of four types of context clues: definition or synonym, example, contrast, and effect. Then the vocabulary test and the context clue tests: versions 1 and 2 were administered to the participants.
The results revealed that (1) context clues hardly benefited the participants in guessing the meanings of the unfamiliar words, (2) vocabulary knowledge and sentence structure knowledge are more essential when it comes to helping learners’ guessing the meaning of unfamiliar words and (3) the students’ difficulties in using context clues to guess the meanings of unfamiliar words included having insufficient vocabulary knowledge, complexity of sentence structures, inability to recognize context clues, a lack of background knowledge, and taking the wrong clues.