Commissioned by the Hsinchu City Youth Chinese Orchestra,“Raining in April Fantasy”was adapted by Lee Che-Yi in 2011 as a concerto for erhu and served as the designated repertoire for the 2011 Taiwanhutopolis Erhu Competition. Originally commissioned by the Taipei Philharmonic Foundation in 2008, “Raining in April Fantasy”was initially a concerto for violin.

“Raining in April Fantasy”consists of three main themes and nine sections, including two cadenzas allowing the players to express their personal styles. The term "fantasy" indicates that “Raining in April Fantasy” was arranged in potpourri form. The source materials for this arrangement are Blushing the Year Round, Sorrow on a Moonlit Night, and Rainy Night Flower by Teng Yu-Hsien. Various composition techniques, such as melodic variation and orchestration adaptation, are used to present the main melody in different forms with rhythmic changes.

The results of the analysis indicate that while the erhu serves as the solo instrument and the rest of the ensemble functions as the orchestra, the main melody is actually performed by both in turn. Therefore, the erhu solo does not lead throughout the entire piece, and the ensemble does not always play the role of the orchestra during the performance. The roles of the erhu and the ensemble switch depending on different phrases. This study uses the orchestral score to present the flow of the melody and provides textual explanations to highlight each variation in the melody. Additionally, in the interpretation of the performance chapter, the author proposes the distinction between two kinds of musical terminology: the "long-line melody" and the "rhythmically driven melody," respectively. These terms help to differentiate between different performance styles and establish boundaries for the performing techniques associated with each style.