Construct a musical piece that follows the designated lettered structure and integrates the provided motif throughout.
X:1
L:1/8
M:4/4
K:C
['FDFA d2', 'f2 (fd) g2 (ge)']  
X:1
L:1/8
M:4/4
K:C
 BEA |[M:2/2][K:D]SOSOO .!fermata!PMTuCO(MAG) | FDFA d2 (fe) | d2 (fd) ecAG | FDFA d2 (fd) | 
 ecAF GBAG | FDFA d2 (fe) | d2 (fd) ecAG | FDFA d2 (fd) | ecAF G2 :: (de) | f2 (fd) g2 (ge) | 
 abag fdde | f2 (fd) g2 (ge) | abaf g2 (fg) | abaf gage | fgfd ecAG | FDFA defd | ecAF G2 :|  