Suppose you are listening to the first movement of a symphony written in the Classical period. If you have heard the first section in which two themes were introduced and a second section in which seg?

you heard the themes developed and transformed, you are likely experiencing the sonata form, which is characteristic of the Classical period. The first section, known as the exposition, presents the main themes, while the second section, the development, explores and varies these themes. After this, you can expect a recapitulation, where the original themes return, often in the home key. This structure creates a cohesive and dynamic musical narrative.