Craft a musical piece that abides by the prescribed structural guidelines and the given theme.
X:1
L:1/8
M:4/4
K:G
['BGBd edge dzBG', 'BGBd eg g2 e a2 f'  
X:1
L:1/8
M:4/4
K:G
 BGBd edge | dzBG AG E2 | BG(3B/c/d edge | dBAc BGG z | BGBd edge | dzBG AGEd | BBGB ABGB | 
 dBAc BGG z :| BGBd eg g2 | e a2 f gedB | GBdB eBdB | ABGB AzGA | BGBd eg g2 | e a2 f gedc | 
 BzGB ABGB | dBAc BGG z :|  