Formulate chord combinations to increase the harmonic complexity of the specified musical excerpt.
G2 BG DGBd | g2 fg edBA | G2 BG DGBG | ABAG FDEF | G2 F2 EDBA | 
 Ggfg edBA | G2 BG DGBd |1 cAFA G4 :|2 cAFA G2 Bc |: dggf gfed | 
 eaag a2 ag | fd d2 ad d2 | faaf gedc | BG G2 EGDF | Ggfg edBA | 
 G2 BG DGBd | cAFA G4 :|  
X:1
L:1/8
M:4/4
K:G
"G" G2 BG DGBd | g2 fg edBA |"G" G2 BG DGBG |"D7" ABAG FDEF |"G" G2 F2"D7" EDBA | 
"G" Ggfg"D7" edBA |"G" G2 BG DGBd |1"D7" cAFA"G" G4 :|2"D7" cAFA"G" G2 Bc |:"G" dggf gfed | 
"Am" eaag a2 ag |"D" fd d2 ad d2 |"D" faaf"D7" gedc |"G" BG G2"C" EGDF |"G" Ggfg edBA | 
 G2 BG DGBd |"D7" cAFA"G" G4 :|  