Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/16
M:2/4
K:C
['E2>C2 B,A,B,2', 'A, [M:3/4] A,2B,>B,', 'A,<A,A,A, B,2A,2 B,2A,2 B,A,A, z ||[M:2/4]', 'B,A,B,2 [M:3/4] B,4- B,A,A,2 A,G,A,2 ||[M:2/4]']  
X:1
L:1/16
M:2/4
K:C
 E2>C2 B,A,B,2 | B,8 | E2>C2 B,A,B,2 ||[M:3/4] B,4- B,A,A,2 A,G,A,2 ||[M:2/4] A,4 z3 A, || 
[M:3/4] A,2B,>B, B,2<A,2 A,<A,A,A, | B,2A,2 B,2A,2 B,A,A, z ||[M:2/4] C2>C2 B,A,B,2 || 
[M:3/4] B,4- B,A,A,2 A,G,A,2 ||[M:2/4] A,8 :|  