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Systemic Drift of L1 Vowels in Novice L2 Learners

Studies of proficient second-language (L2) learners have often noted phonetic drift of their native language (L1) vis-a-vis monolingual norms. Such drift has been attributed to perceptual linkage between similar sounds in L1 and L2. This study provides evidence that L1 phonetic drift is limited neither to advanced L2 learners, nor to cross- language influence at a segmental level. During the first weeks of an elementary Korean class, adult native English speakers were found to shift their English vowel space in approximation to the Korean vowel space, suggesting that in adult L2 learners phonetic drift of L1 vowels occurs in a rapid, systemic, and assimilatory fashion.