Craft a musical piece in accordance with the designated structure and theme.
X:1
L:1/4
M:4/4
K:Dmix
['B G G A']  
X:1
L:1/4
M:4/4
K:Dmix
"^A" B/c/ | d d d e | d3 c | B G G A | F2 D2 | B G G A | B G G A | B G G A | F2 D ||  