Compose a piece using the alphabetic notation of the assigned musical structure and the provided melodic motif.
X:1
L:1/8
M:2/2
K:D
['[DD]2 [DD]2 [DF]2 [DF][DF] [G,G]2 B2 cBAG', 'ag f']  
X:1
L:1/8
M:2/2
K:D
 [DD]2 [DD]2 [DF]2 [DF][DF] | [G,G]2 B2 cBAG | E [=CE]2 [B,E] [CE]2 | =CDEG [FA] [DA]3 | 
 DEFD GAB[GB] | ABcA d2 (3ABc | dcdA BdAG | FDEF D4 :: ag | f [df]2 c [df]4 | fdfg abag | 
 e [=ce]2 [Be] [ce]4 | =cdef g2 ag | f d2 c deag | f d2 A BABc | d2 dA BdAG | FDEF D2 :|  