Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/8
M:4/4
K:C
['c2 (Bc) ABcA GFEF GABd (eg)(fa)', 'e2 agab aged B2 G2 G2 (ef)']  
X:1
L:1/8
M:4/4
K:C
 BEA |[M:2/2][K:A]SOSOO .!fermata!PMTuCO(Med) | c2 (Bc) ABcA | GFEF GABd | (eg)(fa) gedc | 
 B2 G2 G2 (ed) | c2 (Bc) ABcA | GFEF GABd | (eg)(fa) gedB | A2 A2 A2 :: e2 | agab aged | 
 B2 G2 G2 (ef) |{a} gfga gfed | e2 a2 a2 (ed) | c2 (Bc) ABcA | GFEF GABd | (eg)(fa) gedB | 
 A2 A2 A2 :|  