Compose a piece of music following the given alphabetical representation of the musical structure and the provided motif.
X:1
L:1/8
M:4/4
K:G
['', 'BABd cBcA (3dcd (3gfe dBGF EcBc AGFG', 'ca (3aga eaca']  
X:1
L:1/8
M:4/4
K:G
 dc |: BABd cBcA | (3dcd (3gfe dBGF | EcBc AGFG | (3ABA (3GFE DCB,D | BABd cBcA | 
 (3dcd (3gfe dBGF | EcBc AGFG |1 ADFA G3 A :|2 ADFD G2 ga |: bg (3gfg dgBd | bg (3gfg dgBg | 
 ca (3aga eaca | ca (3aga eaca | bg (3gfg dgBd | bg (3gfg dgBg | (3aba (3gag (3fgf (3efe |1 
 decd Bdga :|2 decd Bdgd |]  