本研究延用自主音段音韻學（Goldsmith, 1976）架構，分析台語帶鼻音的後綴詞（例：mi.a「棉仔」，t^h ŋ.a「糖仔」，kim.a「金仔」和p^(h~)i.a「鼻仔」），並藉由F1的聲學變化及一個簡要實驗驗證，進一步釐清台語鼻音性的語音變化現象。研究結果指出：鼻（化）母音的鼻音性懸浮於母音（鼻音承載單位）之上，並可能具雙向擴散功能。因此，「棉仔」、「糖仔」、「金仔」和「鼻仔」在運用可能的鼻音雙向擴散規則之後，其語音表徵可能形態為［mi^(ia~)a］，［t^h ŋ^ (ŋa~)a］，［kim^(ma~)a］和［p^h i^(ia~)a］。

The purpose of this study is to investigate nasality behavior triggered by the suffix a when it is attached to a monosyllabic stem; that is, monosyllabic stem + a, such as mi.a 'cotton', t^h ŋ.a 'candy', kim.a 'gold', and p^(h~)i.a 'nose'. Following the application of the autosegmental model (Goldsmith, 1976) used in previous studies, this paper attempts to offer a possible phonetic representation of the nasality nature. In this study, nasality of nasalized vowels in Taiwanese floats above its nasality bearing vowels and may spread bidirectionally within the domain of a phonological word. The spectrogram of the four words validates the rightward nasality spreading. In addition, a simple test reveals that the leftward nasality spreading may occur. Consequently, the floating nasality may possess the nature of bidirectional spreading. The phonetic realizations of the four words as a result would be transcribed as [mi^(ia~)a] 'cotton', [t^h ŋ^(ŋa~)a] 'candy', [kim^(ma~)a] 'gold' and [p^(~h)i^(ia~)a] 'nose', respectively.