Create a series of chord progressions to improve the harmonic structure of the given music piece.
"^A" d'2bg d2B2 | cee2 F2A2 | cff2 cee2 | dgg2 G2B2 | d'2bg d2B2 | cee2 F2A2 | 
 cff2 fecA | G2B2 G2 z2 :|[K:D]"^B" f^efg afdA | GBeg b2b2 | a^gab c'b=ge | 
 dfad' a2>g2 | f^efg afdA | GBeg b2b2 | a^gab c'b=ge | .d4"_>Teil A" !>!d4 |: 
[K:C]"^C" g6 ^fg | agB2 B2B2 | a6 ^ga | bac2 c2c2 | c'6 bc' | d'c'd2 d2d2 |1 
 baB2 B2B2 | agc2 c2c2 :|2 bad2 agB2 | c2e2 c2 z2"^D" |: d2B2 ffff | 
 e2c2 eeee | g2d2 f2G2 | e2G2 c2E2 | d2G2 ffff | e2c2 eeee | g2d2 f2B2 | 
 c2e2 c2"_Fine" z2 :|  
X:1
L:1/16
M:2/4
K:G
"^A""G" d'2bg d2B2 |"D7" cee2 F2A2 | cff2 cee2 |"G" dgg2 G2B2 | d'2bg d2B2 |"D7" cee2 F2A2 | 
 cff2 fecA |"G" G2B2 G2 z2 :|[K:D]"^B""D" f^efg afdA |"Em" GBeg b2b2 |"A7" a^gab c'b=ge | 
"D" dfad' a2>g2 | f^efg afdA |"Em" GBeg b2b2 |"A7" a^gab c'b=ge |"D" .d4"_>Teil A" !>!d4 |: 
[K:C]"^C""C" g6 ^fg |"G7" agB2 B2B2 | a6 ^ga |"C" bac2 c2c2 | c'6 bc' |"Dm/F" d'c'd2 d2d2 |1 
"G7" baB2 B2B2 |"C" agc2 c2c2 :|2"G7" bad2 agB2 |"C" c2e2 c2 z2"^D" |:"G7" d2B2 ffff | 
"C" e2c2 eeee |"G7" g2d2 f2G2 |"C" e2G2 c2E2 |"G7" d2G2 ffff |"C" e2c2 eeee |"G7" g2d2 f2B2 | 
"C" c2e2 c2"_Fine" z2 :|  