Compose a piece of music that follows both the given musical theme and the letter-based structure provided.
X:1
L:1/8
M:4/4
K:G
['G/A/B/c/ d>B e>deg', 'ga gf/e/']  
X:1
L:1/8
M:4/4
K:G
 g | G/A/B/c/ d>B e>deg | d/c/B/A/ G>B AA/A/ A>B | G/A/B/c/ d>B e>deg | a/g/f/e/ g>d B>B B :| 
 g>a gf/e/ d>e dB | ga gf/e/ dg a>e | ga gf/e/ de/f/ ge | a/g/f/e/ g>d B>B Be | g>a gf/e/ d>e dB | 
 ga gf/e/ d/>e/f/g/ a>e | gaeg dgBg | a/g/f/e/ g>d BB/B/ B ||  