Fantasie was firstly comprised of free improvisatory type and multi-section structure. In the 19th century, the formal structure of sonata and character pieces were combined into the Fantasie. In the process of its evolution, the introduction, slow mid-section, and improvisatory elements which Fantasie includes always play important roles. However, Fantasie varied with different characteristics of individual composers. This paper focuses on three works titled ¡§Fantasy¡¨ from Chopin. It includes five chapters: the first chapter is the introduction. The second chapter is about the historical development of Fantasie in keyboard works. In the third chapter to the fifth chapter Chopin¡¦s Fantaisie-Impromptu Op. 66, Fantasie Op. 49, and Polonaise-Fantaisie Op. 61, and fantastic features of Chopin will be discussed in details.

The late chromatic music of Chopin is often difficult to analyze, particularly with a system of Roman numerals. The study examines Schoenberg's Grundgestalt concept as a strategy for explaining Chopin's chromatic musical style. Two short Chopin works, Nocturne in E-flat major. Op. 9, No. 2, and Etude in E major, Op. 10, No. 3, serve as models in which the analytic method is formulated. Root analysis, in the manner of eighteenth-century theorist Simon Sechter, is utilized to facilitate harmonic analysis of chromatic passages. Based upon the analytic method developed, the study analyzes the last three polonaises of Chopin: Polonaise in F-sharp minor, Op. 44, Polonaise in A-flat major, Op. 53, and Polonaise-Fantasie in A-flat major, Op. 61. The Grundgestalt-based analysis shows harmonic, melodic and rhythmic connections in order to view Chopin's chromaticism and formal structure from a new perspective. With this approach, the chromaticism is viewed as essential to the larger form.