Allophonic Variation in L1 and L2 English Laterals: Evidence from L1 Japanese-L2 English Speakers

Second language (L2) learners often face a number of obstacles in acquiring target-like speech production patterns. This study examines L1 Japanese speakers' production of L2 English /l/ to investigate how they implement position-dependent allophonic variation while overcoming mismatches between Japanese (L1) and English (L2) in (1) the number of liquid phonemes, (2) their allophonic distributions, and (3) syllable structure. Acoustic and articulatory (ultrasound) analyses of word-initial and word-final English /l/ produced by thirteen L1 Japanese-L2 English speakers and nine L1 English speakers show that L1 Japanese-L2 English speakers produce target-like lateral allophony acoustically, although their lateral production is overall clearer (i.e., less velarised) than that of L1 English speakers. By contrast, L1 Japanese-L2 English speakers' articulation is non-target-like, characterised by different tongue shape dimensions and the absence of coronal-dorsal timing patterns found in L1 English speakers' production. Overall, the results highlight the complex nature of L2 speech production, in which L2 speakers utilise a wider range of phonetic cues to overcome learning challenges than is commonly assumed.