Compose a piece adhering to the given musical structure and theme.
X:1
L:1/8
M:4/4
K:G
['c2 dc', 'dg g2 dgBc dgag'  
X:1
L:1/8
M:4/4
K:G
 B3 d c2 dc | BGGF DE=FD | GABd c2 dc | BGAF G3 A :| dg g2 dgBc | dgag fdcB | c=f f2 cfAf | 
 c=fag ^fdcA | dg g2 dgBc | dgag fdef | gbag fdeg | fdca G4 ||  