The feature of tenseness is distinctive in English vowels but not in Korean vowels. This makes Korean students difficult to learn English tense and lax vowels. The purposes of this study are to investigate how correctly Korean learners can perceive En...
The feature of tenseness is distinctive in English vowels but not in Korean vowels. This makes Korean students difficult to learn English tense and lax vowels. The purposes of this study are to investigate how correctly Korean learners can perceive English tense /i/, /u/ and lax vowels /ɪ/, /ʊ/, to observe how correctly Korean learners can pronounce them by carrying out the perception test of native listeners of English, and finally to find out the difficulties in perceiving and pronouncing them in Korean learners and to give them information for good pronunciation.
This study carried out two kinds of the perception experiments.
In Korean learners' perception experiment, 20 students in elementary school participated, and 16 words including /i/-/ɪ/ and /u/-/ʊ/ minimal pairs were chosen to be tested. The stimuli that native speaker of English had pronounced were recorded. Korean students were asked to choose one of the four choices on the worksheet while they were listening to the recordings.
In English native speakers' perception experiment, the subjects were four Korean students in elementary school and ten native listeners of English working at elementary school. The same words were used as the stimuli. The stimuli that four students had pronounced were recorded. Native listeners of English were also asked to judge and to choose one of the four choices while they were listening to the recordings.
The result of the first experiment shows that Korean learners perceived the back lax vowel /ʊ/ better than the other vowels /i/, /ɪ/, and /u/. The reason for that is the front vowels /i/ and /ɪ/ have three distinctive features ([+high], [+front], [±tense]), whereas the back vowels /u/ and /ʊ/ have a lip rounding feature as well as three distinctive features ([+low], [+back], [±tense]). It is likely that the lip rounding feature gave Korean students the additional cue to perceive the back vowels easier than the front vowels. In addition, Korean vowel /우/ requires the lip rounding and the tension less than /u/ when it is pronounced. Thus, Korean learners may think Korean vowel /우/ and the back lax vowel /ʊ/ have some similarities in pronouncing them.
The result of the second experiment shows that native listeners perceived Korean learners pronounced the lax vowels /ɪ/, /ʊ/ better than the tense vowels /i/, /u/. F1, F2 values and vowel durations of tense and lax vowels were measured to confirm how Korean speakers had pronounced them, and then to compare them with those of native speakers of English. The results of formant frequencies show that there was no difference between the tense and lax vowels of Korean speakers. They produced tense and lax vowels in the nearly same area whereas Native speaker of English pronounced those vowels in two separate spots. The results of the vowel durations show Korean students pronounced tense vowels shorter than those of native speakers of English, whereas they pronounced lax vowels as short as those of native English speakers. Therefore, it is likely that the native speakers of English relied more on the vowel durations while they were identifying the lax vowels pronounced by Koreans speakers. On the other hand, Native speakers of English may have trouble in perceiving tense vowels due to incorrect formant frequencies and shorter durations of tense vowels.
In conclusion, Korean students lacked an appropriate level of pronouncing and perceiving ability to discriminate between English tense and lax vowels. It is necessary that Korean students practice the correct movement of the lips, tongue, and jaw when they pronounce English tense and lax vowels understanding the differences of the vowel systems between Korean and English.