Compose a piece of music that follows both the given musical theme and the letter-based structure provided.
X:1
L:1/4
M:4/4
K:Dmin
['G A']  
X:1
L:1/4
M:4/4
K:Dmin
|:"Dm" D D/C/ D F |"G" G3 D |"Gm" G G/F/"C" G A |"Dm" F3 z |"Bb" F F/E/ F G |"C" E3/2 D/ C2 | 
"Am" E E/D/ E F |"Dm" D3 z ::"Dm" A A/G/ A F |"G" G3 D |"Gm" G G/F/ G A |"Dm" F3 z | 
"Gm" G G/F/ G A |"Dm" F3/2 E/ D2 |"C" E E/D/ E F |"Dm" D3 z :|  