Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/4
M:4/4
K:G
['d B']  
X:1
L:1/4
M:4/4
K:G
"^A" D |"G" G2 G3/2 G/ |"G" G2"D7" A c |"G" B2 B3/2 B/ |"G" B2"C" c e |"G" e d B d |"D7" d c A F | 
"G" G2"C" G3/2 G/ |1"G" G D"D7" B, :|2"G" G3 ::[M:3/4]"^B" B/c/ |"G" d B g/e/ |"G" d B e/d/ | 
"D7" c A B/A/ |"G" G/F/G/A/B/c/ |"G" d B g/e/ |"G" d B e/d/ |"D7" c A F |"G" G2 :: 
[M:4/4]"^C" B/c/ |"G" d B g e |"G" d B G B |"D7" d c A c |"G" e d B B/c/ |"G" d B g e | 
"G" d B G B |"D7" d c A F |"G" G3 :|  