Develop a musical composition in line with the given structure and theme.
X:1
L:1/4
Q:1/4=180
M:2/4
K:Bbdor
['B F', 'f f/f/ f', 'f f/f/ f'  
X:1
L:1/4
Q:1/4=180
M:2/4
K:Bbdor
|: B F | B F | A B/c/ | B _A/G/ | B F | B F | A B/c/ | B _A/G/ | B F | B F | A B/c/ | B _A/G/ | 
 c c/c/ | c/B/c/d/ | c B | z2 :: c/d/ e | f f/f/ | f f/f/ | f z | c e | c c/c/ | c B/B/ | B z :: 
 c/d/ e | f f/f/ | f f/f/ | f z | c e | c c/c/ | c B/B/ | B z :|  