Spell the colour chords

Diminished and augmented chords move the 5th but keep its LETTER. C major has G; C diminished has G♭; C augmented has G♯. All three are a kind of G, because the 5th is always four letters up.

Suspended chords are the opposite: they replace the 3rd with a real neighbour, so the letter genuinely changes. Csus4 is C, F, G — an F where the E used to be.

A few augmented chords cannot be written with single accidentals at all — F♯ augmented would need a C double-sharp — so those are left out, the same way D♯ major was.

dim/aug: same letters, moved 5th — sus: a different letter

C augmented: the 5th is still a G, sharpened. C dim would be G♭.

Practise this in the trainer — it opens with this lesson the first time the concept comes up.