Develop a musical composition using the outlined alphabetical depiction of the structure and the provided theme.
X:1
L:1/8
Q:1/8=150
M:4/4
K:G
['BGBd gfga bage', 'G2 ga bagb (3aba ga baga a2']  
X:1
L:1/8
Q:1/8=150
M:4/4
K:G
 ge | dBAB GAGA | BGBd gfga | bage dBGB | (3ABA GB A2 ge | dBAB G3 A | BGBd gfga | bage dBAB | 
 G2 GG G2 :| ga | bagb (3aba ga | baga a2 ga | b2 ba gedB | A2 AA A2 ge | dBAB GAGA | BGBd gfga | 
 bage dBAB | G2 GG G2 :|  