Create music using the given musical theme and adhere to the outlined letter-based structure.
X:1
L:1/8
M:6/8
K:Bb
['F B2 Bccc fff c2']  
X:1
L:1/8
M:6/8
K:Bb
 f | edcBBB | ccc F2 F | B2 Bccc | fff c2 F | B2 Bccc | fff c2 F | B2 Bccc | fff c2 f | edcABB | 
 ccc F2 F | BB/B/BABc | f3 c2 |]  