歌劇自十六世紀末於義大利誕生以來，能夠入樂的文字不是散文，而是 本身就已經有種韻律與節奏感的「韻文」(verse)。隨著義大利歌劇在十七、 十八世紀的歐洲造成跨國界的風行，義語歌劇劇本中韻文結構與其配樂的方 式，亦逐漸形成一定的模式與傳統，此傳統甚至影響其他語種歌劇劇本的韻 文編寫方式。1781 年，莫札特(Wolfgang Amadeus Mozart, 1756-1791) 在創 作其德語歌劇《後宮誘逃》(Die Entführung aus dem Serail, 1782) 時寫下： 「對音樂而言，韻文是最不可或缺的。」這句話說明的，不僅是他譜曲《後 宮誘逃》的原則，更多的是他從義語歌劇習得的認知。因為，德語歌劇在十 八世紀尚未建立起自己的韻文入樂傳統，且莫札特到此時已經譜曲過八部義 語歌劇。本文的目標在於，以義語韻文格律中最重要的兩個特色：「音節數」以及「結尾重音」，來闡明義語歌劇劇本韻文之於音樂「不可或缺的」關係。藉由選例於莫札特的三部維也納時期義語諧劇，本文亦提供一個途徑，理解莫札特韻文入樂之思考：「歌劇裡，詩必須是音樂乖順的女兒」。

Since opera first emerged in the late sixteenth century in Italy, verse, instead of prose, was chosen to be set to music because it contains rhythm and meter. With the prominence of Italian opera in Europe during the seventeenth and eighteenth centuries, the setting of verse developed a unique mode and tradition which influenced the versification of libretti in other languages. Mozart (1756-1791) claimed in 1781 that “verse is indispensable to music,” when he was composing his German Singspiel Die Entführung aus dem Serail (1782). The quote is based upon not only his personal principle in his composition of Die Entführung aus dem Serail, but also from his experiences with Italian operas. In the 18th century when German opera had not yet established its own tradition of setting verse to music, Mozart had already composed eight Italian operas by 1781. This article examines two of the most significant elements in Italian versification, namely, the number of syllables and the final accent of the verse line, in order to illuminate how verse in Italian libretto is “indispensable to music.” With examples from Mozart’s three Viennese opera buffas, this article also discusses Mozart’s inspiring comment on setting verse to music, “In an opera, the poetry must be the obedient daughter of the music.”