Craft a piece of music that integrates both the suggested theme and letter-based structure.
X:1
L:1/8
M:4/4
K:D
['AF F2 DFAd BG G2', 'ceag fd']  
X:1
L:1/8
M:4/4
K:D
 B | Aafg efdB | AF F2 DFAd | BG G2 EFGE | FA (3AAA FAAf | agfg egdB | AF F2 DFAd | BG G2 EGAG |1 
 FAag fd dB :|2 FAag fd df || a2 fd Adfd | gfed cAAf | a2 fa bfed | Beed efge | f3 a g3 e | 
 faef dBAG | FA (3AAA GBed |1 ceag fd df :|2 ceag fd dB ||  