Compose a piece of music that follows both the given musical theme and the letter-based structure provided.
X:1
L:1/8
Q:1/4=120
M:4/4
K:G
['AGAB AGEF GAGE DEGB', 'G2 uD2 GABc d2 ef gfge dBGB']  
X:1
L:1/8
Q:1/4=120
M:4/4
K:G
"^Irish Reel." uB2 | c2 dc B2 cB | AGAB AGEF | GAGE DEGB | AGAB AGEB | ccec BBdB | AGAB AGEF | 
 GAGE DEGB | AGAB G2 |] uD2 | GABc d2 ef | gfge dBGB | c2 ec B2 dB | AGAB (AG) E2 | gage dBGB | 
 AGAB AGEF | GAGE DEGB | AGAB G2 |]  