The phonological system of Khalkha Mongolian includes /ɮ/ and /r/. It is generally assumed that these are phonologically placed in liquids, and that /ɮ/ and /r/ are realized as the voiced dental lateral fricative ɮ and the voiced dental trill r, respectively. However, these phonetic descriptions have not been sufficiently confirmed through acoustic analyses, especially regarding their voiceness. In addition, the phonological statuses of /ɮ/ and /r/ have not been adequately considered on the basis of phonological phenomena. This study addresses the phonetic and phonological characteristics of Mongolian /ɮ/ and /r/ through acoustic analyses and by observing phonotactic patterns. In conclusion, this study claims that Mongolian /ɮ/ and /r/ have distinct characteristics in voicing, sonority, and phonotactic restriction. According to the acoustic analyses, /ɮ/ is normally realized as the voiceless ɬ even in the intervocalic position and can be fully or partially voiced because of the voicing of the adjacent vowels, whereas /r/ is essentially pronounced as voiced r. In addition, the phonetic realization of stop + liquid sequences reveals that /ɮ/ is voiceless and has lower sonority, and thus, it does not form a syllable with the preceding stop, while /r/ is voiced and has higher sonority, so it functions as a syllabic consonant. From the perspective of phonotactics, /ɮ/ and /r/ differ in their acceptability in word-initial position.
Naoki Ueta (Sun,) studied this question.
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