Hyekyung Sung

Degree of foreign accent in English sentences produced by Korean children and adults

The purpose of this longitudinal study was to evaluate the influence of age (adult vs. child) and length of residence (LOR) in an L2-speaking country (3 vs. 5 years) on degree of foreign accent in a second language (L2). Korean adults and children living in North America, and age-matched groups of native English (NE) adults and children, recorded English sentences in sessions held 1.2 years apart (T1 vs. T2). NE-speaking listeners rated the sentences for overall degree of perceived foreign accent using a 9-point scale. The native Korean (NK) children received significantly higher ratings than the NK adults did, but lower ratings than the NE children. The NK children—even those who had arrived as young children and been enrolled in English-medium schools for an average of 4 years—spoke English with detectable foreign accents. The effects of LOR and the T1–T2 differences were non-significant for both the NK adults and the NK children. The findings were inconsistent with the hypothesis that adult–child differences in L2 speech learning are due to the passing of a critical period. The suggestion is made that the milder foreign accents observed for children than adults are due, at least in part, to the greater L2 input typically received by immigrant children than adults.

A developmental study of English vowel production and perception by native Korean adults and children

Abstract This study examined the production and perception of English vowels by native Korean (NK) learners of English on two occasions separated by about 1 year. A preliminary experiment revealed that NK adults classified some pairs of contrastive English vowels using two different Korean vowels whereas other pairs showed classification overlap, implying they would be difficult for Korean learners of English to discriminate. In two subsequent experiments, NK adults and children differing in length of residence in North America (3 vs. 5 years; 4 groups of 18 each) were compared to age-matched native English (NE) speakers. In Experiment 2, NK children were found to discriminate English vowels more accurately than NK adults but less accurately than NE children. In Experiment 3, English words containing /i ɪ e ɪ e ae ɑ ʌ/ were elicited using a picture-naming task. Some vowels produced by NK children were heard as intended significantly more often than vowels produced by NK adults. Acoustic analyses revealed that NK children produced significantly larger between-vowel contrasts than NK adults but did not differ from NE children. Taken together, the results suggested that although children are more successful than adults in learning the phonetic properties of second-language vowels, they might continue to differ from age-matched native speakers in certain respects as uncovered by the vowel discrimination test in Experiment 2.

Release Bursts in English Word-Final Voiceless Stops Produced by Native English and Korean Adults and Children

The aim of this study was to evaluate the acquisition of statistical properties of a second language (L2). Stop consonants are permitted in word-final position in both English and Korean, but they are variably released in English and invariably unreleased in Korean. Native Korean (K) adults and children living in North America and age-matched native English (E) speakers repeated English words ending in released tokens of /t/ and /k/ at two times separated by 1.2 years. The judgments of E-speaking listeners were used to determine if the stimuli were repeated with audible release bursts. Experiments 1 and 2 revealed fewer final releases for K than E adults, and fewer releases for /t/ (but not /k/) for K than E children. Nearly all /t/ and /k/ tokens were heard as intended in experiment 3, which evaluated intelligibility. However, the K adults’ /k/ tokens were identified with less certainty than the E adults’. Taken together, the results suggested that noncontrastive (i.e., statistical) properties of an L2 can be learned by children, and to a somewhat lesser extent by adults.

Release bursts in English word‐final stops: A longitudinal study of Korean adults’ and children’s production

Stops at the end of Korean words are always unreleased. The question addressed here was whether Korean adults and children living in the U.S. can learn to release stops at the end of English words. Four groups of 18 native Koreans (NK) who differed according to age (adult versus child) and length of residence in the U.S. (3 vs 5 years at T1) participated. Two native English (NE) groups served as age‐matched controls. Production data were collected at two times (T1, T2) separated by one year. English words ending in /t/ and /k/ were then examined in perception experiments (Exp. 1, Exp. 2). NE‐speaking judges decided whether the final stop has a release burst or not. Exp. 1 showed that NE talkers released /t/ more often than NK talkers did. The effect of time was also significant. Talkers produced release bursts more often at T2 than at T1. Exp. 2 showed that, unlike Exp. 1, there were significant differences between NK adults and children. While NK children did not differ from NE children, NK adults releas...

The pronunciation of English sentences by Korean children and adults

This study examined English sentences produced by four groups of native Korean subjects (18 each) who differed according to mean age (children=12 years, adults=32 years) and length of residence in North America (means=3 vs 5 years). A delayed repetition technique was used to elicit English sentences at Time 1 and one year later at Time 2. Native English‐speaking listeners used a 9‐point scale to rate the sentences for overall degree of foreign accent. The ratings obtained for the native Korean (NK) subjects were converted to z‐scores using the mean ratings and standard deviations obtained for sentences produced by control groups of Native children and adults. As expected, analyses of the standardized ratings revealed that the NK children produced the sentences with milder foreign accents than the NK adults did at both Time 1 and Time 2. Unexpectedly, the adult–child difference was larger at Time 2 than Time 1 because the NK children’s foreign accents diminished whereas the NK adults’ foreign accents grew ...