Stuck trying to decode the harmony of Blue Bossa for school. Chords (5th edition Real Book; 6th is unnecessarily complicated) C-7/C-7/F-7/F-7 D-7(b5)/G7/C-7/C-7 Eb-7/Ab7/DbMaj7/DbMaj7 D-7(b5)/G7/C-7/D-7(b7)G7 The key signature is written with 3 flats (Bb, Eb, and Ab), which is of course Eb Maj. I labeled C-7 as Vl-7, F-7 in turn as ll-7, and D-7(b5) is Vll-7(b5). The G7 is non-diatonic, and although I see it serving as a dominant for the C-7, I'm not sure what to call it, or what it subs for. Anybody up on this stuff and knows what to call that G7 in harmonic analysis terms? I see the Eb-7/Ab7/DbMaj7 as a ll/V7/IMaj7 that is simply an abrupt modulation before the song returns to its (mostly) diatonic chord progression. Anybody? Much obliged!