Utilizing the provided musical theme and letter-based structure, compose a piece of music.
X:1
L:1/8
Q:1/8=128
M:4/4
K:Bb
['FB/c/dB FG>BF>BF>Bd/c/ B/c/dcc dB/c/dB']  
X:1
L:1/8
Q:1/8=128
M:4/4
K:Bb
 FB/c/dB FG>BF>BF>Bd/c/ B/c/dcc | dB/c/dB FG>BF>BG>BG/F/E/D/ C2 B, | 
 FB/c/dB FG>BF>BF>Bd/c/ B/c/dcc | dB/c/dB FG>BF>BG>BG/F/ E/D/ C2 B, | dB>Bd Bf>Bd | 
 fe>gd>fg/f/e/d<cd<BB/d Bf>Bd | fe>gg/f/e/d/ c2 B | dB>Bd Bf>Bd | 
 fe>gd>fg/f/e/d<cd/B/c/dB FG<Be<gf>bg/f/ e/d/ c2 B |]  