Questions: Functional Harmony: Tonic, Subdominant, and Dominant

Question 1

In C major, which chord serves the Dominant function?

• A. IV (F major)
• B. I (C major)
• C. ii (D minor)
• D. V (G major)

Answer: (D)

The Dominant function is served by V and vii°. In C major, V is G major. The Dominant creates the strongest tension in tonal harmony because it contains the leading tone (B in C major), which pulls urgently back to tonic. IV is Subdominant, I is Tonic, and ii is also Subdominant.

Question 2

In functional harmony, a minor chord typically serves the Subdominant function.

• T. True
• F. False

Answer: False

Harmonic function depends on context, not chord quality. In C major, vi (A minor) serves the Tonic function — it shares two notes with I and provides a sense of rest. The ii chord (D minor) serves Subdominant. Even vii° (diminished, which could be considered 'minor-like') serves Dominant. Chord quality and harmonic function are independent dimensions.

Question 3

Why can the ii chord substitute for the IV chord in a Tonic–Subdominant–Dominant–Tonic progression?

Model answer: Both ii and IV share the same Subdominant function — they create motion away from tonic stability and prepare the Dominant. They also share two common tones (in C major, IV = F-A-C and ii = D-F-A share F and A), so the substitution produces a similar harmonic color with slightly more tension.

Functional harmony is about what a chord does, not which chord it is. Any chord in the Subdominant family (IV or ii) can fulfill the S slot in the T–S–D–T cycle. The common tones between ii and IV make the substitution smooth, and ii tends to feel slightly more active because it has no tonic note, making it a popular choice before a dominant cadence.