Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/8
Q:3/8=110
M:6/8
K:D
['def ecA Bcd', 'A3 =cBA BGG G3 BGB dcB cAA']  
X:1
L:1/8
Q:3/8=110
M:6/8
K:D
 def ecA | Bcd BAG | FAB AFD | CDE E3 | def ecA | Bcd cBA | dcB cBA | BE^G A3 :: AFD"^*" =cBA | 
 BGG G3 | BGB dcB | cAA A3 | ecA gfe | fag fed | gfe fed | eAc d3 :|  