Final answer:
The three sections of Sonata-Allegro Form are Exposition, Development, and Recapitulation, where themes are introduced, manipulated, and then restated in a resolved manner.
Step-by-step explanation:
The three sections of Sonata-Allegro Form are: Exposition, Development, and Recapitulation. In the Exposition, the main themes are presented, often in contrasting styles. The Development section then manipulates these themes through various techniques, creating tension and expectation. The Recapitulation returns to the themes as presented in the Exposition but typically resolves the tension, often in the original key.