Craft a musical work based on the specified structure and given theme.
X:1
L:1/8
M:4/4
K:Bb
['B>c B<F{Bc}', 'f>gfd ed gf'  
X:1
L:1/8
M:4/4
K:Bb
 d/c/ | B>c B<F{Bc} d<B Bd/c/ | B>c B<F{Bc} d>c cd/c/ | B>cBF dc ed | f>g f/g/f/e/ dB B :| d/e/ | 
 f>gfd ed gf | B>dfd g/f/e/d/ cd/e/ | f>gfd cBdc | B>G F/G/B/c/{Bc} d>B Bd/e/ | f>gfd ed gf | 
 B/c/d/e/ f/g/a/b/ g/f/e/d/ c/d/e/f/ | gf ed cB dc | B>G F/G/B/c/{Bc} d>B B ||  