Craft a musical work adhering to the specified theme and structure.
X:1
L:1/4
M:2/4
K:G
['B G']  
X:1
L:1/4
M:2/4
K:G
 B/ | B B/B/ | B/G/G/G/ | G E | E E | A A | d/c/B/c/ | B G | G D | G D | G A | B A | c d | B A | 
 B G | A B | G z/ |]  