本文以Goldsmith (1976)所提出的自主音段音韻學架構分析三個臺語詞 彙「金鴨」、「金仔」、「金馬」的語音表徵形式。由語音聲學、發音、 及聽覺感知分析結果顯示，三詞彙[m]時長在統計上呈現顯著性差異。然 而，莫拉理論在應用上卻有其侷限性；它或許可解釋日語詞kita [ki(μ)][ta(μ)]與 kitta[kit(μ)(μ)][ta(μ)]的時長差異，卻無法解釋 臺語詞「金仔」[kim(μμ)ma(μ)]與「金馬」[kim(μμ)][ma(μ)]的時長差 異。因此本文乃提出連音「二空缺」及「雙向同化規則」來解釋此時長差 異，即：時長差異乃導因於不同韻律單位的語音轉折，因此三詞彙的[m]時 長差異即為「金鴨」[kim][a?] vs•「金仔」[kimmaa] vs•「金馬」[kim]H[ma]。

This paper examines the phonetic representations of the three Taiwanese words kim al ‘golden duck’, kim a ‘gold’, and kim ma ‘place name’ under the autosegmental framework (Goldsmith 1976). In accordance with the acoustic, articulatory, and perceptual analyses, the durational differences of the three [m] s across the three words have been shown to be different. However, the moraic theory may be limited to the contrast of the three words (e.g., [kim(μμ)ma(μ)] ‘gold’ vs. [kim(μμ)][ma(μ)] ‘place name’) though it may be applicable to only the contrast of [CV(μ)][CV(μ)] (Japanese kita ‘arrived’) vs. [CV(μ)(μ)][CV(μ)] (kitta ‘sliced’). As a result, the double-empty slots (xx-slots) and the bidirectional assimilation rule are proposed to explain such disparity. In my proposal, I state that the length differences are attributed to phonetic transition across different prosodic boundaries; the durational contrast of the consonant [m] therefore can explicitly be observed from the surface forms of [kim][‘a?] ‘golden duck’ vs. [kimmaa] ‘gold’ vs. [kim]=[ma] ‘place name’.