I–IV–V–I
I – IV – V – I
I – IV – V – I
Example: In C Major (Ionian): C – F – G – C
The purest diatonic cadence: tonic stability, subdominant color, dominant tension, and return home. Countless beginner songs are built from these three functions.
- C C – E – G
- F F – A – C
- G G – B – D
- C C – E – G