Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/8
M:6/8
K:Gmin
['', 'A BAG DGA BAG c2 B A^FD', 'B A^FD']  
X:1
L:1/8
M:6/8
K:Gmin
 A |: BAG DGA | BAG c2 B | A^FD CDE | D^FD d2 A | BAG DGA | BAG c2 B | A^FD CDE |1 D^FD G2 A :|2 
 D^FD GBd || g3 d3 | edc d2 B | A^FD cA^F | dAd ^fd^f | g^fg dBd | edc d2 B | A^FD c3 |1 
 AG^F GBd :|2 AG^F G2 A ||  