Craft a piece of music that integrates both the suggested theme and letter-based structure.
X:1
L:1/8
M:3/8
K:Bb
['F BDG GFB/c/ d>Bd/c/ c2 F eec']  
X:1
L:1/8
M:3/8
K:Bb
 F | BDG | GFB/c/ | d>Bd/c/ | c2 F | eec | ddB | c>eA | B2 |]  