Formal analysis here means one that examines the overall structure. Although form may seem to be different from harmony, the latter should be included in a formal analysis. Thus, formal analysis should include an examination of the harmonic structure, the melodic structure, motives, rhythm, variation techniques, and especially the relationships between small and large scale structures. Motives are the smallest recurring linear units, from one to several notes long. Subjects are one to eight measures in length and are composed of motives.
Themes are the longest units, from four to several measures long.
The motive and phrase often form the basis of the small scale building blocks, or cells , in a composition. Thus, this is a good place to begin. Although phrases can be of any length, the 2 or 4-bar phrase is a standard length found in most music and is used as a point of departure. Phrases combine to form sentences, and sentences combine to form periods. Periods combine to form double-periods.