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:G
['E G']  
X:1
L:1/4
M:4/4
K:G
"G" D3/2 E/ D E | G A B2 |"Am" A G E G | B A"D" B/ d3/2 |"G" D3/2 E/ D E | G A B3/2 c/4B/4 | 
"C" A G"Am" E C |"D" D4 ::"G" d2 d3/2 e/ | d c B2 |"C" A G E G |"D" B A B/ d3/2 | 
"G" d3/2 B/ d3/2 e/ |"Em" d c B3/2 c/4B/4 |"C" A G"Am" E C |"D" D4 :|  