Two phrases or periods can be combined to create a simple two-part form, or binary form. Three phrases or periods combine to create a simple three-part form, or ternary form. A more complex structure with one or more simple part forms used as one of the sections is referred to as a composite part form.
To delineate phrases, lower-case letters are used. Upper-case letters are used to define parts or sections. A two-part form with contrasting periods is represented by the letters A-B, while a two-part form with similar periods is represented by the letters A-A’. If the form is ternary, and the third section is identical to the first, the form is designated as A-B-A. If part of the A section returns, but not all of it, it is referred to as rounded binary, or incipient ternary. This might be described as A-B-A’.
There are three commonly used formal elements used by composers of all types of music that might be considered auxiliary to the primary content. These are Introductions, Transitions, and Endings. An introduction is used to set the tone, key, and rhythmic features of a piece before the actual themes are introduced. A transition smoothly prepares the listener for new material in a different harmonic area, or a return to earlier material. The ending, or coda (Italian word for “tail”) is often appended to impart a sense of finality to the piece, or to a section of a piece.
A composition based on a single phrase or melodic idea may be referred to as a one-part form. An example of this type is the Chopin Prelude Op. 28, No. 20, found on page 258 in the Anthology section. An Analysis Exercise with a score is included in the Materials below. While it has three distinct sections, it is based on a single rhythmic and melodic motive with other factors elaborating the shape of the piece.
The Chopin Muzurka Op. 7, No.1, discussed on page 90 of the text is a simple five-part composition. The score is on page 261 of the Anthology section, and a link to a performance on YouTube is included in the Materials below. Complete a Graphic Analysis Form of this composition, along with a page of Analytic Observations. The ABACA structure is referred to as a Rondo, however each section of this piece is a simple form. Note that the repeats do not alter the form, and do not impact the essential structural components.
Example 4-3, page 79: J. S. Bach, French Overture, Bourree I, Binary, ms. 1-24
Example 4-4, page 80: Schubert Waltz, Op. 9, No. 3, Rounded Binary, ms. 1-16
Example 4-11, page 90: Chopin, Mazurka, Op. 7, No. 1, Five-Part Form, ABACA
The score is on page 261.