Formulate a musical piece by utilizing the specified motif and alphabet-based structure.
X:1
L:1/8
M:3/4
K:F#min
['BA G4']  
X:1
L:1/8
M:3/4
K:F#min
 C A G | FF GA BA | G4 AB | c2 c>B ce | c3 c cB | A2 c2 BA | G4 FG | BA GF GA | F3 |]  