Compose a piece of music that follows both the given musical theme and the letter-based structure provided.
X:1
L:1/8
Q:1/8=160
M:6/8
K:D
['dAF AFD ABA AFD GBG FAF', 'D2 F/E/ DFA dcd efe ecA Bee']  
X:1
L:1/8
Q:1/8=160
M:6/8
K:D
 (3A/B/c/ | dAF AFD | ABA AFD | GBG FAF | EFA B2 A | dAF AFD | ABA AFD | GBG FAF | EDE D2 :| F/E/ | 
 DFA dcd | efe ecA | Bee ede | fdd d2 A | ded dcB | AdB AFD | GGG FEF | EDE D2 :|  