Compose a piece of music that follows the specified structure and incorporates the given theme.
X:1
L:1/4
M:6/4
K:D
['A,2 G,']  
X:1
L:1/4
M:6/4
K:D
 D | =C2 _B, A,2 G, | =F,3/2 E,/D,/E,/ C z E, | =F,2 F, G,2 A, | A,2 G, A, z D | =C2 _B, A,2 G, | 
 =F,3/2 E,/D,/E,/ C z E, | =F,2 F, G,2 A, | A,2 G, A, z A, | =C G, _B,/A,/ A,2 A, | 
 G,3/2 =F,/ E, F, F, A, | B,2 C D3/2 E/ =F | E3/2 D/ C D D |]  