戲劇是綜合性表演藝術，為提高觀眾欣賞興致，能快速吸納各種民間表演藝術特長，是涵融性極高的舞臺藝術。《貨郎旦》雜劇第四折將搖鼓說唱的民間藝術寄寓於九轉【貨郎兒】中。此劇以正宮九轉【貨郎兒】曲段夾入南呂【一枝花】套的異宮夾套，因形式特殊而受人矚目；豐富的轉調歌唱音樂，為人所喜愛。明代朱有燉以《義勇辭金》、《仙官慶會》襲用「轉調貨郎兒」之曲段作劇，改為本宮夾套；清代洪昇《長生殿‧彈詞》以《貨郎旦》異宮夾套體九轉【貨郎兒】譜曲後，將九轉【貨郎兒】的雜劇體式納入傳奇，為歌場所傳唱。此劇開啟擬作風氣。戲曲曲套音樂具有明顯的程式性特徵。《貨郎旦》之異宮夾套形式在元明之際具有創新曲套的意義，為明清至民國曲家創作劇本所襲用。本文探討以九轉【貨郎兒】組套的劇作十三種。在歸納後，逐一討論以九轉【貨郎兒】為曲段的曲套音樂程式，分析此一音樂程式的形成、發展與變化。發現某些劇作已有由完全承襲《貨郎旦》體或《義勇辭金》體而演為南北合腔聯套的變化，這是南北曲交化後，演為成熟北套，而又再次南曲化的現象。研究以九轉【貨郎兒】組套之劇作的發展，可以瞭解戲曲程式性音樂套式成熟的過程。戲曲音樂程式在加入人物、演唱方法、劇情情節、舞臺時空流轉等等多重變因後，可以讓本應固定的音樂模式顯得變化無窮，是程式規律裡表現「死法活用」的創意關鍵。

In terms of stage performance, opera is a broad and wide comprehensive cultural reservoir in the traditional Chinese Opera History . In the fourth scene of ”A Woman Peddler Singer” sang in a Chinese Cheng-Kong Melody in nine-modulation-tune connected talking and beat rhythm. Highly attractive modulation style, followed interesting song had been welcomed by the audience completely. The playwright Chu Yu-Tun in the Ming Dynasty used the melody ”Peddler Singer” in his works ”A Righteousness Hero Refused Gold Reward” and ”Fairy Official Celebration” in a variety. The Playwright Hung Sheng in Qing Dynasty adopted the love story of Tang Hsuan Chung and his concubine Yang Kuei-Fei, in a modulation melody of ”Peddler Singer” to work. The opera melody style of ”A Woman Peddler Singer” of Yuan Dynasty mixed the dram style of Ming Dynasty up, caused the audience attention and continued spreading in the opera-house out, found a fashionable imitation atmosphere. From Ming and Qing Dynasty until Republic Era continued this music tune: the drama ”Woman Peddler Singer” developed in the opera style with nine-modulation-tune as a typical opera melody basis. This research explored thirteen kinds of nine-modulation-tune of ”Peddler Singer”. Being induced, I discussed their musical tune step by step carefully, studied their musical form, development process and variety thoroughly. The melody of ”A Woman Peddler Singer” and the melody of ”The Righteousness Hero Refused Gold Award” had been recomposed and reorganized in the style of Northern Chu (Melody) or the Southern Chu (Melody) soon and obtained an integrated unit successfully. When the Northern Chu (Melody) formed and organized in the Southern Chu (Melody) together, reached to the high point of the Northern Chu (Melody), in the mean while, had been strengthened the Southern Chu (Melody) phenomenon fully. When I concentrated on the drama ”Peddler Singer”, found the traces of Chinese Opera development process, comprehended its music melody and organized a basic formula system. A basic opera melody with figure, singing technique, story action, plot detail, performance stage and difference, could be demonstrated its simple music structure and variety clearly. ”Starting a story line with additional melody in multiple levels”, appeared a work creation essence naturally.