Ternary Form

'In Three Parts'

The basic structure for ternary form is: ABA

Often each section repeats so it becomes: AABBAA

• Section A ends in the main key, usually with a perfect cadence so it sounds like a complete piece itself.
• Section B modulates to a related key, i.e. the dominant or relative minor, before returning to the main key at the end.
• When the music returns to the A section it can vary slightly from the original A section, i.e. with ornatmentation.
• If it varies it could be called A1, but it shouldn't be so…