The major pentatonic scale is formed by a major triad (1 -3 -5) with the addition of the 2nd and 6th of the major scale. You can use it in major, minor and dominant chords. For each major key exists the relative minor which has the same alterations so, for each major pentatonic correspond a minor pentatonic. Since all the notes are the same, the minor pentatonic is simply an inversion or a mode of the major pentatonic.
C Major Pentatonic
C Major Pentatonic: C D E G A – A Minor Pentatonic: A C D E G
Different pentatonics can be applied over the same chord to create extensions or alterations. There are many possibilities, the following are just some
Cmaj7 = Root, 2, 5 = C Maj Pentatonic, D Maj Pentatonic, G Maj Pentatonic.
Cmin7= b3, b7, 4 = Eb Maj Pentatonic, Bb Maj Pentatonic and F Maj Pentatonic.
C7 = Root, b3, 4, b7 = C Maj Pentatonic, Eb Maj Pentatonic, F Maj Pentatonic and Bb Maj Pentatonic.
Major Pentatonic shape
Minor Pentatonic shape
How to practice
Set up a loop and take a groove, every 4 repetitions play a fill using one of the exercises and try all the pentatonics available over a chord. Some exercises will sound more musical than others but the point here is to work on Fretboard Skills, Groove & Fills and Applied Harmony at the same time.
Here some Pentatonic fills I transcribed from different players.