Utilizing the provided musical theme and letter-based structure, compose a piece of music.
X:1
L:1/8
Q:1/8=350
M:12/8
K:D
['B2 A', 'f2 e dcd']  
X:1
L:1/8
Q:1/8=350
M:12/8
K:D
 B2 A Bcd B2 A F2 A | B2 A Bcd e3 e2 d | B2 A Bcd B2 A F2 A | AGF D2 F E3 E3 :| 
 f2 e dcd B2 A d2 e | f2 e dcd e3 e3 | f2 e dcd B2 A d2 B | AFA D2 F E3 E3 :|  