The first measures of Mozart's Sonata K. 283 in G Major are an excellent example of how the I (tonic), IV (subdominant) and V (dominant) degree chords can be used. Since we are in the key of G Major, G major is the tonic, C major is the subdominant and D is the dominant.

In the first measures, Mozart plays the chords using arpeggios (the notes are played consecutively). He also uses chord inversions. When a chord is in inversion the lowest note is not the root. For example, in measure 2, Mozart uses a D dominant 7th chord (D - F# - A - C), but he uses the A as the lowest note (see Inversions).

In the next example we have:

1. Added a top stave with all chords in root position and the chord symbol (see Triads Chord Symbols in Jazz, 7th-chord Symbols in Jazz).
2. Added roman numerals below the lowest stave to identify the degrees. Chord inversions are shown using the small numbers (see Baroque Chord Symbols, Figured Bass 7th-chord Symbols).
3. The notes in red are non-harmonic tones. These notes are not part of the chords.

 

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