Japanese speakers learning r and l

Japanese has one liquid phoneme /r/, realized usually as an apico-alveolar tap [ɾ] and sometimes as an alveolar lateral approximant [l]. English has two: an alveolar lateral approximant /l/ and a rhotic consonant /r/ of varying phonetic properties centered on the alveolar or postalveolar approximant [ɹ]. Japanese speakers who learn English as a second language later than childhood often have difficulty in hearing and producing /l/ and /r/ of English accurately.

The Japanese liquid is most often realized as an alveolar tap [ɾ], though there is some variation depending on phonetic context./r/ of American English (the dialect Japanese speakers are typically exposed to) is most commonly a postalveolar central approximant with simultaneous secondary pharyngeal constriction and lip rounding: [ɹ̠ˤʷ], though it may also be a labialized retroflex approximant [ɻʷ]./l/ involves contact with the alveolar ridge as well as some raising of the tongue dorsum (velarization), especially when syllable-final.

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