Construct a music composition that complies with the designated structure and theme.
X:1
L:1/8
M:2/4
K:G
['g2 fa', 'f2 ed'  
X:1
L:1/8
M:2/4
K:G
|:"^A" d2 BB | B3 G | AAAB | dc B2 | g2 fa | g2 fa | gdcB | B2 A z ::"^B" A2 Ac | BBBd | dAAc | 
{/c} B3 d | f2 ed | f2 ed | gd =f/e/d/c/ | B2 MA2 | G4 :|  