Changing tone

Give a complete definition for the following types of nonharmonic tones. Your answer should include a description of the approach and resolution, plus any directional tendencies that must be included to fully describe these tones.

A changing tone is a pair of nonharmonic tones that appear between two chord tones, usually on a weak beat. The first of the pair moves stepwise away from the chord tone, followed by a leap in the opposite direction to another nonchord tone. The pattern is resolved by a step in the opposite direction back to the original chord tone.