Watch the Major Triads online guitar lesson by John Stowell from Modern Jazz Improv

At approximately 4:40 in this segment, I misspoke: as I was demonstrating the major triads that can be superimposed over dominant chords and summarizing the available keys, I played an Eb major triad and called it an E major triad. As with the other applications of triad substitutions, take each individual triad and combine it with the original dominant. Then work on triad pairs or combining triads with melodic or harmonic minor substitutions for a variety of sounds/colors/tensions.