Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/16
M:2/2
K:Gmin
['G4 D8 A2B2 G8 B8 A4 F4', 'G8 G6 Bc d6 Bc d4 B4']  
X:1
L:1/16
M:2/2
K:Gmin
 G4 D8 A2B2 | G8 B8 | A4 F4 f4 c4 | A8 c8 | B4 G4 d4 g4 | ^f8 d8 | (e2d2)(c2B2) (A2B2) c4 | 
 B8 G8 |] G6 Bc d6 Bc | d4 B4 G4 B4 | A6 AB c6 AB | c4 A4 F4 f4 | d6 ga b6 ag | a4 g4 ^f6 =e^f | 
 g4 a4 a6 g2 | g8 d6 BA |]  