Abstract Using comparative evidence from the three Sakishima (South Ryukyuan) languages, Miyakoan, Yaeyaman and Dunan, this paper postulates a reconstruction of two Proto-Sakishima *a-initial diphthongs, *ao and *au, and argues that this distinction was carried over to Proto-Miyakoan and Proto-Yaeyaman. The number of vocabulary items traceable to Proto-Sakishima *au is scarce and almost exclusively involves morphologically complex forms, mostly verbs, making the *ao and *au distinction one easy to omit or disregard as random sound change irregularities. Furthermore, most of the modern Sakishima regiolects have lost the distinction between *ao and *au, Tarama-Miyakoan being the only one that consistently maintains the original distinction in all relevant areas of vocabulary and not just verbs, reflecting *ao as /au/ or /oː/ and *au as /uː/. Positing Proto-Sakishima *ao and *au in accordance with the Tarama reflexes begets new insights concerning the *o > *u raising in Sakishima as well as in Ryukyuan in general, thus confirming the slow gradualness of the process and hinting at the chronology of the changes related to this raising. It also reveals a number of specifics concerning the diachrony of Sakishima verb systems, especially the development of conclusive verb forms, thus explaining the apparent discrepancy in *au and *ao reflexes in the regiolects of Miyako and Yaeyama.

中文翻译：

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较大图片的精细细节：原始日本岛* au和* ao diphthongs

摘要利用来自三种岛南（琉球南）语言Miyakoan，Yaeyaman和Dunan的比较证据，本文假定对两种原始-Sakishima * a初始双元音* ao和* au进行了重构，并认为这种区别被延续了到Proto-Miyakoan和Proto-Yaeyaman。可以追溯到原始日本语岛* au的词汇数量很少，几乎只涉及形态复杂的形式，大部分是动词，这使得* ao和* au的区别很容易被忽略或忽略，因为随机声音变化不规则。此外，大多数现代Sakishima区域语已经失去了* ao和* au之间的区别，Tarama-Miyakoan是唯一一个在所有相关词汇领域而不是仅在动词上都保持原始区别的人，将* ao反映为/ au /或/oː/和* au为/uː/。根据Tarama反射将原始sakishima * ao和* au定位会获得关于Sakishima和Ryukyuan中* o> * u上升的新见解，从而证实了这一过程的缓慢渐进性并暗示了与这次筹款有关的变化。它还揭示了有关Sakishima动词系统历时的许多细节，尤其是结论性动词形式的发展，从而解释了宫古和八重山地区的* au和* ao反射的明显差异。