Craft a musical piece that abides by the prescribed structural guidelines and the given theme.
X:1
L:1/8
M:6/8
K:D
['d2 A dcd', 'eee f2 e ccc d2 c AAA', 'FFF FFF', 'fff fff'  
X:1
L:1/8
M:6/8
K:D
 A | d2 A dcd | ede faf | d2 A dcd | efe dcB | d2 A dcd | ede faf | A2 d e2 d | cBc d2 || 
 !fermata!e | eee f2 e | ccc d2 c | AAA B2 A | G3 F2 d | eee f2 e | ccc d2 c | AAA B2 A | G3 F2 || 
 D | FFF FFF | FFF FFF | GGG GGG | GGG GGG | AAA AAA | AAA AAA | F2 G F2 G | A2 d A2 || d | 
 fff fff | fff f2 B | dcB dcB | c2 F F2 d | fff fff | fff f2 B | dcB dcB | f3 f2!D.C.! ||  