Craft a piece of music that integrates both the suggested theme and letter-based structure.
X:1
L:1/8
Q:1/4=90
M:2/4
K:G
['gf ef ed B2 (GB) (AB) (AF)', 'B2 E2 E2 GA Bc d2 (BA)']  
X:1
L:1/8
Q:1/4=90
M:2/4
K:G
"_vb" gf | ef ed | B2 (GB) | (AB) (AF) | D2 (EF) | G2 (AG) | E2 E2 | (E4 |"^Fine" D2) || B2 | 
 E2 E2 | GA Bc | d2 (BA) | G2 A2 | B2 e2 | d2 f2 | e4- |"^DC al Fine" e2 |]  