Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
M:6/8
K:F
['F F2']  
X:1
L:1/8
M:6/8
K:F
 F | F2 c(cd) c | B2 A(GA) B | c2 F F2 G/G/ | A2 c c2 F | F2 c(cd) c | B2 A G2 (A/B/) | c2 F FFG | 
 (A2 c) c2 c | (AG) A(FG) A | (GF) G C2 C | F2 F F2 G/G/ | A2 A c2 (c/B/) | (AG) A(FG) A | 
 (GF) G C2 e | f2 F F2 G/G/ | A2 A c2 ||  