Compose a piece of music that follows both the given musical theme and the letter-based structure provided.
X:1
L:1/8
M:6/8
K:G
['g dBG GFG BAB', 'g gAg gfe aAa agf']  
X:1
L:1/8
M:6/8
K:G
 g | dBG GFG | BAB GFG | dBG ABd | e2 A A2 g | dBG GFG | BAB GAB | gfe dBA | B2 G G2 :| g | 
 gAg gfe | aAa agf | gag gfe | a2 e e2 g | gAg gfe | aAa agf | gfe dBA | B2 G G2 :|  