Articulatory characteristics and vowel space analysis of Mandarin Chinese non-low vowels in Korean-speaking learners

Vowels are a fundamental component of Mandarin Chinese syllables. Accurate pronunciation of Mandarin Chinese relies on the distinct articulation of different vowels, especially the visually similar "ü" and "u". Korean-speaking learners of Chinese Mandarin as a second language commonly exhibit non-standard pronunciation or errors in articulating "ü", leading to confusion, particularly in non-low vowels centered around this sound. Using Praat to analyze the Formant values of non-low vowel sounds from six participants, a comparison between Korean L2 Chinese speakers and native Chinese speakers revealed vowel spaces differentiated through F2 values for /u/ and /o/, while /ɣ/ and /o/ are distinguished by F1 values. The sound similar to Korean "ㅟ" differs from /y/ in that the former is a gliding sound transitioning from low to high. The distinction between /y/ and /u/, /o/, /ɣ/ was found to be unclear, with /y/ often merging into sounds like "iu" and "io". This aligns with historical vowel changes in Chinese "ü", noted in previous linguistic studies, showing variations like "iu" and "io" over different periods. Korean L2 Chinese speakers tend to substitute /ɯ/ for /u/ and "ㅟ" (/ɯ/+/i/) for /y/, avoiding rounded lip movements in pronunciation, thus reducing effort and the need for additional phonemes. Furthermore, the F3 value for Korean L2 Chinese /y/ is notably lower, suggesting that the correct articulation should closely resemble the tongue position of /i/, combined with rounded lips.