Develop a musical composition in line with the given structure and theme.
X:1
L:1/8
Q:1/8=125
M:4/4
K:D
['A2 d2', 'f g/f/e/d/{d} c2 (d/e/f/g/) a2 g2 f/d/g/e/'  
X:1
L:1/8
Q:1/8=125
M:4/4
K:D
"^Key shown as G major" A2 | d2 d2 d/e/f/g/ ad | e2 e(f/g/) f3 e | (ed)(ed) (fg)(fg) aefc | 
 de/f/ ed{d} c z2 |"^1" z Aec (ag/f/) (e/d/c/B/) | A2 B2 A2 :: d2 dA BG z f | 
 g/f/e/d/{d} c2 (d/e/f/g/) | a2 g2 f/d/g/e/ a/f/e/d/ | A2 e2 d2 ::  