Map 1 shows the distribution of the retroflex initials in the synchronic perspective . it is suggested that seemingly " weird " sound changes have been produced as reactions in terms of a general tendency for de - retroflextion 笔者认为，卷舌音声母在不少地区正处于趋向消失的过程中，而对此趋势的反作用则在某些地区产生了似乎不很正常的语音变化。
2.
The present paper demonstrates the structure of a phonetic and phonological data - base called rtfl , which provides synchronic and diachronic information on retroflex initials as well as on structurally related initials in chinese dialects 本文介绍了有关卷舌音声母的一种数据库，称为Ｒ Ｔ Ｆ Ｌ 。此数据库的基本原则是“符号化” ，即以数字或罗马字代表各项语音或音韵特徵。
3.
He has also shown how electronic technology can be harnessed to map out and account for phonological developments in china through the example of retroflex initials . mitsuaki endo follows the admirable tradition of toiling with patience and perseverence to provide a foundation that will facilitate research by others . he has compiled frequency data on initials , medials ( glides ) , nucleus vowels , rhyme endings and tones in the chinese rhyme book 远藤光晓经过长期艰苦的努力，对《广韵》中所出现的音位(声母、介音、主要元音和声调)进行了统计，并求出了各音位及各种语音类别的频率，为今后从计算与计量的角度研究从中古到现代各方言的语音演变过程及原因提供了量化的依据。
