In music theory and composition, form refers to the structure of a piece. Since music is a temporal art form (it happens over a duration of time), the order in which ideas are presented is of the upmost important. Music theory students tend to spend a large portion of their early studies on how musical form works on small and large scales. Here are some important terminology in the study of musical form:
Phrase – A phrase is the smallest section of musical form. It typically consists of 4-8 measures and ends with a cadence, or resting point. It’s the smallest section of music that gives the impression of a complete thought.
Sentence – A sentence is a type of phrase with a specific structure. It begins with a melodic motive that is then repeated or transposed to a different pitch and then followed with a different idea ending in a cadence.
Period – A period consists of two or more phrases that are strung together with the strongest cadence occurring at the end of the final phrase. Periods are typically eight or more measures long.
Now that we understand how to breakdown smaller sections or periods, how do we go about distinguishing and labeling these different periods?