Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/8
Q:1/4=120
M:3/4
K:C
['G2 c2']  
X:1
L:1/8
Q:1/4=120
M:3/4
K:C
 G2 |"C" c2 G2 c2 | e4 dc |"G" d2 G2 d2 | f4 ed |"C" e2 cd ef | g2 fe dc |"G" dB G2 F2 | 
"C" F2 E2 G2 |"C" c2 e2 dc |"G" ed cB AG |"C" c3 e dc |"G" c2 B2 GG |"F" AB c2 BA | 
"G" Bc d2"D7" e^f |"G" g2 dc BA | G4 dd |"G" d2 cB AG |"G7" d3 e f2 |"Am" e2 dc BA |"E7" e4 e2 | 
"Am" a2 ed cB |"F" cB AB cA |"G" de fe dc |"G7" BA GA BG |"C" cB cd ef | g3 f e2 |"G7" f2 e2 d2 | 
"C" c4 |]  