Compose a piece of music that follows both the given musical theme and the letter-based structure provided.
X:1
L:1/8
M:3/8
K:Gdor
['GBc dfe cBG d>ef gfe d>ef', 'c3 gfd fdc dcB cBG GBd c>Bc']  
X:1
L:1/8
M:3/8
K:Gdor
 GBc | dfe | cBG | d>ef | gfe | d>ef | gfe | c3 :| gfd | fdc | dcB | cBG | GBd | c>Bc |1 def | 
 ecd :|2 dcB | G3 |]  