Craft a musical work based on the specified structure and given theme.
X:1
L:1/8
Q:3/8=90
M:6/8
K:Bb
['f b2 f d>cB c>dc A>GF f>gf', 'f2 c A>Bc F>fe d>ef B>ba g>ag'  
X:1
L:1/8
Q:3/8=90
M:6/8
K:Bb
 f | b2 f d>cB | c>dc A>GF | f>gf g>de | d>cB B2 f | b2 f d>cB | c>dc A>GF | f>gf =ecf | 
 f2 =e f2 :: c | A>Bc F>fe | d>ef B>ba | g>ag ^fdg | g2 ^f g2 a | bfd gec | fdB ecA | dBG cAf | 
 d>cB B2 :|  