previously discussed I–IV–V chord progressions of major triads is a subsequence of the circle progression, which ascends by perfect fourths and descends by perfect fifths: Perfect fifths and perfect fourths are inverse intervals, because one reaches the same pitch class by either ascending by a perfect fourth (five semitones) or descending by a perfect fifth (seven semitones). For example, the jazz standard "Autumn Leaves" contains the iv7–VII7–VIM7–ii7–i circle-of-fifths chord progression; its sevenths occur in the tertian harmonization in sevenths of the minor scale. Other subsequences of the fifths-circle chord progression are used in music. In particular, the ii–V–I progression is the most important chord progression in jazz music. Chord chart guide for major inversions Major inversions for guitar in standard tuning. The low E is on the left. The A demonstrates three of the different movable shapes. A: [XXX655] | A: [XXX9(10)9] | A: [XXX220] B: [XXX442] C: [XXX553] D: [XXX775] E: [XXX997] F: [XXX211] G: [XXX433] Specific tunings Standard tuning: minor and major sevenths Besides the dominant seventh chords discussed above, other seventh chords—especially minor seventh chords and major seventh chords—are used in guitar music. Minor seventh chords have the following fingerings in standard tuning: Dm7: [XX0211] Em7: [020000] Am7: [X02010] Bm7: [X20202] Fm7: [202220] or ([XX2222] Also an A/F Chord) Major seventh chords have the following fingerings in standard tuning: Cmaj7: [X32000] Dmaj7: [XX0222] Emaj7: [021100] Fmaj7: [103210] Gmaj7: [320002] Amaj7: [X02120] Major-thirds tuning In major-thirds (M3) tuning, the chromatic scale is arranged on three consecutive strings in four consecutive frets. This four-fret arrangement facilitates the left-hand technique for classical (Spanish) guitar: For each hand position of four frets, the hand is stationary and the fingers move, each finger being responsible for exactly one fret. Consequently, three hand positions (covering frets 1–4, 5–8, and 9–12) partition the fingerboard of classical guitar, which has exactly 12 frets. Only two or three frets are needed for the guitar chords—major, minor, and dominant sevenths—which are emphasized in introductions to guitar-playing and to the fundamentals of music. Each major and minor chord can be played on exactly two successive frets on exactly three successive strings, and therefore each needs only two fingers. Other chords—seconds, fourths, sevenths, and ninths—are played on only three successive frets. Advanced chords and harmony Sequences of thirds and seconds The circle of fifths was discussed in the section on intermediate guitar chords. Other progressions are also based on