Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
M:4/4
K:C
['F2 F2', 'A8 B3 B B2 BB B2 FF']  
X:1
L:1/8
M:4/4
K:C
[M:4/4][K:Bb]!p! e da ad ba e!p! e!p! a b!>!d ave ec!p! ucbbe be a e ug e e a ad uf e ca due dua eede ua d ua d ua!p!e[Q:1/4=120] F2 | 
 d2 d2 c2 cA | B B B2 D2 D D | FF F2 F2 F2 | B6 F2 | d2 dd c2 cA | B2 BB D2 DD | E2 EE F2 F2 | 
 B,8 | B,2 C2 D2 E2 | FF F2 F2 FF | BB B2 B2 B2 | A8 |: B3 B B2 BB | B2 FF D2 F2 :|  