Craft a musical composition that incorporates the supplied alphabet sequence and motif.
X:1
L:1/8
M:2/4
K:F
['FGF_E F2 G z _EFGF- F_EC z']  
X:1
L:1/8
M:2/4
K:F
 FGF_E | F2 G z | _EFGF- | F_EC z | B,CEC | FF C2 | B,2 C z | _ECFE- | EC F2- | F4 |]  