Construct a musical composition utilizing the provided motif and conforming to the specified structure.
X:1
L:1/8
M:4/4
K:Amin
['D2 C3', 'D2 C3 A, _B,2'  
X:1
L:1/8
M:4/4
K:Amin
|: C2 EDED E2 | D2 C3 B, A,2 | D2 C3 A, _B,2 | G,2 A,6 :: D2 C3 A, _B,2 | D2 C3 A, _B,2 | 
 D2 C3 A, _B,2 | G,2 A,6 :|  