Formulate chord combinations to increase the harmonic complexity of the specified musical excerpt.
d/c/ | d D F A | B/A/B/c/ d e | f/g/ a B/c/ d | e3/2 f/ e c | d D F A | 
 B/c/ d c a/g/ | f d e c | d2- d :: f/g/ | a f- f a | f d- d e/f/ | 
 g/f/e/d/ c d | e3 f/g/ | a f d f | A d F A | d3/2 e/ e3/2 d/ | d3 :|  
X:1
L:1/4
Q:1/2=80
M:2/2
K:D
 d/c/ |"D" d D F A |"G" B/A/B/c/"A" d e |"D" f/g/ a"G" B/c/ d |"Em" e3/2 f/"A" e c |"D" d D F A | 
"G" B/c/ d"A" c a/g/ |"D" f d"A" e c |"D" d2- d :: f/g/ |"D" a f- f a |"Bm" f d- d e/f/ | 
"Em" g/f/e/d/ c d |"A" e3 f/g/ |"D" a f d f |"Bm" A d F A |"D" d3/2 e/"A7" e3/2 d/ |"D" d3 :|  