Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/16
Q:1/8=120
M:3/4
K:G
['D2G2B2 D2G2B2 d2c2A2', '(3ded ^cded']  
X:1
L:1/16
Q:1/8=120
M:3/4
K:G
|: D2G2B2 D2G2B2 | d2c2A2 F4 E2 | D2F2A2 D2F2A2 | d z ^cded B6 | D2G2B2 D2G2B2 | d2c2A2 E2G2 FE | 
 D2F2A2 c2B2A2 |1 (3GAG F GBd g6 :|2 (3GAG F GBd g4 e2 || (3ded ^cded gf ed^cd | gf ed^cd F6 | 
 (3ded ^cded =c'b agfe | (3ded ^cded B4 e2 | (3ded ^cded gf ed^cd | gf ed^cd F6 | 
 (3ded ^cded fe d=cBA | (3GAG FGBd g6 :|  