Craft a musical piece that abides by the prescribed structural guidelines and the given theme.
X:1
L:1/8
Q:1/4=140
M:4/4
K:G
['g2 dB cBce', 'efge fgaf'  
X:1
L:1/8
Q:1/4=140
M:4/4
K:G
 d | g2 dB cBce | (dg)Bd cA A2 | g2 dB cBce | dBcA G/G/G G :: d | (ef).g.e (fg).a.f | 
 (gf).g.a (be).e.g | efge fgaf | gedc BGGg | efge fgaf | gfga beef | gdbf gdec | BdAc BGG :|  