Compose tunes based on the given letter-based musical structure and the supplied motif.
X:1
L:1/8
M:4/4
K:Amix
['e2 ec A2 ce g2 fe dGBd', 'Aaga ecAc']  
X:1
L:1/8
M:4/4
K:Amix
 e2 ec A2 ce | g2 fe dGBd | e2 ce aece | g2 dB A2 AB :: Aaga ecAc | Bdge dBGB | Aaga ecAc | 
 g2 dB A2 AB :|  