Craft a musical piece in accordance with the designated structure and theme.
X:1
L:1/8
M:4/4
K:G
['B,2 B,C DB, G,2 CDEG cBAF GABd', 'dBGB dgfg'  
X:1
L:1/8
M:4/4
K:G
 B,2 B,C DB, G,2 | CDEG cBAF | GABd g2 fg | ecAG FEDC | B,2 B,C DB, G,2 | CDEG cBAF | GABd g2 fg | 
 ecAF G3 B :: dBGB dgfg | ecAc e2 dc | BGBd g2 fe | (3fgf (3efe d3 e | dBGB dgfg | ecAF GFED | 
 GBdB cBAG | FGAF G4 :|  