Skip to main content
United StatesMusic TheorySyllabus dot point

How do we add passing and neighbor tones to decorate a chord progression without breaking voice-leading rules?

Topic 6.2 Writing Passing Tones and Neighbor Tones: add passing and neighbor tones to a part-writing texture correctly and without creating parallels.

A focused answer to AP Music Theory Topic 6.2, covering how to add passing and neighbor tones to a four-voice texture, choosing where a third can be filled with a passing tone, decorating a static voice with a neighbor, and avoiding parallels caused by the embellishment, with a worked addition.

Generated by Claude Opus 4.89 min answer

Reviewed by: AI editorial process; not yet individually human-reviewed

Have a quick question? Jump to the Q&A page

Jump to a section
  1. What this topic is asking
  2. Adding a passing tone
  3. Adding a neighbor tone
  4. Why added tones must be checked for parallels
  5. Adding an embellishment
  6. Try this

What this topic is asking

The College Board (Topic 6.2) wants you to add passing and neighbor tones to a four-voice texture correctly: fill a third with a passing tone, decorate a held or repeated note with a neighbor, and do so without creating parallel fifths or octaves through the new motion.

Adding a passing tone

A passing tone needs exactly a third-sized gap to fill. If two chord tones are a step apart there is nothing to fill, and if they are a fifth apart a single passing tone will not bridge them.

Adding a neighbor tone

Because the neighbor returns to its starting note, it is the natural way to add motion to a voice that would otherwise just hold, without changing the underlying harmony.

Why added tones must be checked for parallels

The central idea is that an embellishing tone introduces new motion, and any new motion can accidentally create the parallel fifths or octaves the voice-leading rules forbid. A passing tone that moves one voice through a fifth or octave with another voice on consecutive strong points can produce parallels that were not there before. The safe strategy is to decorate one voice at a time while the others hold their chord tones, so the new tone moves against stationary voices and cannot form parallels with them. When two voices must both move, check the intervals at each note of the decoration, not just at the chord changes. This discipline is what separates a tasteful decoration from a voice-leading error, and it is exactly what the composition free-response question rewards: melodic interest added without breaking the rules.

Adding an embellishment

To add a passing or neighbor tone, identify a voice that either spans a third (for a passing tone) or holds a note (for a neighbor tone), insert the stepwise decoration, keep the other voices on their chord tones, and check that no new parallels appear at any point of the added motion.

Try this

Q1. What size of gap between two chord tones does a single passing tone fill? [1 point]

  • Cue. A third; the passing tone supplies the stepwise note between the two chord tones.

Q2. Why is it safest to decorate one voice while the others hold their chord tones? [2 points]

  • Cue. Moving one voice against stationary voices cannot create parallel fifths or octaves with them, so the decoration stays rule-compliant.

Exam-style practice questions

Practice questions written in the style of College Board exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.

AP 2022 (style)1 marksSection I (multiple choice, written). To add an unaccented passing tone in a voice, between which two notes should the voice move? (A) two chord tones a third apart (B) two chord tones a fifth apart (C) the same repeated chord tone (D) two notes already a step apart
Show worked answer →

The correct answer is (A) two chord tones a third apart.

A passing tone fills the gap between two chord tones that are a third apart, supplying the stepwise note in between (for example C to E filled by a passing D). The two chord tones must be a third apart so that a single passing step fits between them.

(B) a fifth apart is too wide for one passing tone. (C) a repeated note has no gap to fill. (D) notes already a step apart leave no room for a passing tone. The trap is trying to insert a passing tone where there is no third-sized gap; the passing tone needs exactly a third to bridge.

AP 2023 (style)3 marksSection II (free response, part-writing). Over a I chord held for two beats in C major, add an upper neighbor tone in the soprano (which holds G) and explain how to keep the other voices free of parallels.
Show worked answer →

A 3-point part-writing question.

(1 point) The soprano on G (the fifth of C major) can take an upper neighbor: G steps up to A and back to G while the chord is held.
(1 point) The lower three voices keep their chord tones (C, E and a doubled tone) sustained or repeated under the neighbor motion, so only the soprano decorates the harmony.
(1 point) Because the neighbor tone A is brief and the other voices do not move with it, no new parallel fifths or octaves are created; the embellishment sits over a static accompaniment.

Markers reward a correctly shaped neighbor (G up to A and back), keeping the other voices on chord tones, and noting that holding the accompaniment prevents parallels from the added tone.

Related dot points

Sources & how we know this