Develop a musical composition in line with the given structure and theme.
X:1
L:1/8
M:6/8
K:Bb
['D G G']  
X:1
L:1/8
M:6/8
K:Bb
 G/A/ | B3 G A F | D G G G2 G/A/ | B3 A G F | D F F F2 D | G G A B B c | d e d d2 c | 
 B A G D =E F | G2 G G2 ||  