Formulate chord combinations to increase the harmonic complexity of the specified musical excerpt.
D | D G A | B2 G/F/ | E c c | c2 B/c/ | d3/2 G/ G | G F G | A3- | 
 A z D/D/ | D G A | B2 G/F/ | E c c | c2 c/c/ | B3/2 A/ G | F G A | G3- | 
 G z2 || d3 | c B3/2 A/ | B3- | B z D/D/ | G3/2 G/ G | G F G | A3- | 
 A z D/D/ | D G A | B2 G/F/ | E c c | c2 c/c/ | B3/2 A/ G | F G A | G3- | 
 G z |]  
X:1
L:1/4
Q:1/4=132
M:3/4
K:G
 D |"G" D G A |"G" B2 G/F/ |"C" E c c |"C" c2 B/c/ |"G" d3/2 G/ G |"G" G F G |"D7" A3- | 
"D7" A z D/D/ |"G" D G A |"G" B2 G/F/ |"C" E c c |"C" c2 c/c/ |"G" B3/2 A/ G |"D7" F G A |"G" G3- | 
"G" G z2 ||"G" d3 |"D7" c B3/2 A/ |"G" B3- |"G" B z D/D/ |"G" G3/2 G/ G |"G" G F G |"D7" A3- | 
"D7" A z D/D/ |"G" D G A |"G" B2 G/F/ |"C" E c c |"C" c2 c/c/ |"G" B3/2 A/ G |"D7" F G A |"G" G3- | 
"G" G z |]  