Phonetic Features Influencing Native English Speakers and Korean EFL Teachers’ Comprehensibility and Accentedness Judgments

The purpose of this study was to investigate and compare the phonetic features that influence the judgments of comprehensibility and accentedness made by native English speakers (NESs) and Korean English teachers (KETs). Further, it discusses implications for pronunciation instruction and assessment in Korean EFL context. Adapted from Yang’s (2021) research design, 10 NESs and 10 KETs each rated comprehensibility and accentedness for 30 speech samples, and the researcher analyzed which phonetic features of the speech samples influenced their judgments. The results of a multiple regression analysis revealed that the predictors of NESs’ comprehensibility judgments were the number of syllable structure errors and VarcoV, which is one of rhythm metrics, while the predictors of their accentedness judgments were the number of syllable structure errors, the number of segmental errors, and articulation rate. KETs were influenced by articulation rate, the number of syllable structure errors, and VarcoV when they made judgments on comprehensibility and accentedness. Based on the results, the guidelines for English pronunciation instruction and assessments conducted in Korean EFL contexts are suggested.