Coda-r in De'ang:Its Nature and Historical Evolution
In this study,we present the synchronic distribution,an acoustic analysis of the phonetic features,and an internal comparison of the coda-r in De'ang.We argue that the coda-r in De'ang is in nature a retroflex approximant[(t)],which has a relatively long interval and is pronounced quite independently from adjacent vowels.The coda-r existed in ancient De'ang syllables with long vowels.Its being a retroflex approximant made it unstable as a coda,which has disappeared in most dialects of present-day De'ang.Its being a retroflex approximant has also caused its evolution along two distinct paths:one is its evolving into the coda-n,which,just as-r,is also a continuant and a coronal and thus has a retention effect on the long vowels;the other is its evolving into the high back vowels u or ɯ,which show a close relationship with the coda-r because of the retroflex gesture,or its causing the backing or heightening of the main vowels preceding it.The evolution of the coda-r is subjected to the influence of the disappearing of vowel length distinction.In terms of the chronological sequences of sound evolution,the change from-r to-n occurs earlier than that from-r to vowels.