Craft a piece of music that integrates both the suggested theme and letter-based structure.
X:1
L:1/8
M:6/8
K:G
['G2 A B2 c', 'f2 d']  
X:1
L:1/8
M:6/8
K:G
 G | G2 A B2 c | d2 e f2 d | B2 B f2 d | cAc F2 F | G2 A B2 c | ded b2 a | gfe d=e=f | (g3 g2) :: 
 g | g2 a b2 g | f2 d f2 d | BcB g2 d | cAc F2 G/F/ | G>AG B2 c | d>ed b2 a | gfe d=e=f | g3 g2 :|  