Major 7th chords are constructed from the P1 (root), M3 (major 3rd), P5 (perfect 5th), and M7 (major 7th) intervals of the major scale.

major 7 chord root on 6

maj7 Chord – Form 6

major 7 chord root on 5

maj7 Chord – Form 5

major 7 chord root on 5

maj7 Chord – Form 3

major 7 chord root on 4

maj7 Chord – Form 2

major 7 chord root on 4

maj7 Chord – Form 1