Formulate chord combinations to increase the harmonic complexity of the specified musical excerpt.
|: A2 A Ace | agf ecA | A2 A Ace | BGE ECA, | A2 A Ace | agf ecA | 
 dfd ecA | EBG A3 :: E2 A AcA | BdB BGE | E2 A AcA | dBG A3 | 
 E2 A AcA | BdB BGE | BdB AcA | dBG A3 :|  
X:1
L:1/8
M:6/8
K:A
|:"A" A2 A Ace |"D" agf"A" ecA |"A" A2 A Ace |"E7" BGE"A" ECA, |"A" A2 A Ace |"D" agf"A" ecA | 
"D" dfd"A" ecA |"E7" EBG"A" A3 ::"A" E2 A AcA |"E7" BdB BGE |"A" E2 A AcA |"E7" dBG"A" A3 | 
"A" E2 A AcA |"E7" BdB BGE |"E7" BdB"A" AcA |"E7" dBG"A" A3 :|  