以層級投射看天津方言的連讀變調

A Percolative Account of Tianjin Tone Sandhi

天津方言中三連調的變化規律無論對優選論還是傳統的推演都構成很大的挑戰。若以推演的方式進行，則需要制定推演中途方向轉移的裝置；若以優選論進行解釋則會遇上透明與非透明現象相纏的死結。本文建議以層級投射的辦法來解決問題：結構樹中結點與結點之間所含信息必須有所對應，因而最低結點的音系訊息自然出現向上投射的效果。這個對應在一般情況下完全一致，但如果投射產生標記性，那麼對應可能會出現偏差。這個理論需要我們重新考慮語音的呈現形式，並且帶來四種預期效果：(1) 方向性可以從結構推衍出來；(2) 非透明性的深度與結構的層級有直接關係；(3) 音系規則的作用針對的是同屬一個音系單位的語音成分，不是相鄰的語音成分，所以出現變調組合時，如果兩個音節分屬不同單位經常可以維持不變調；(4) 深層的音段可分別以兩種形式同時在表層上出現。

This paper presents data from Tianjin tritonal sandhi patterns that challenge both traditional derivational approaches and standard Optimality Theoretic (OT) approaches to phonological alternation. If construed derivationally, Tianjin tritonal sandhi requires derivational reversals; but if construed within OT, involves combinations of opacity and transparency. The account proposed here appeals to a percolative model where phonological information from terminal nodes finds correspondences in higher nodes, such that the correspondences may be imperfect when triggered by markedness requirements. While this requires a total reconceptualization of phonological representations, this paper argues that it is well worth it because it predicts that: (1) directionality is a derivate from branching; (2) the depth of derivational opacity is confined by structural depth; (3) constituency, not adjacency, provides the environment for triggering alternation so alternation rules can therefore be blocked when marked collocations belong to different constituencies; and (4) underlying entities can have split surface correspondences.