Compose a piece using the specified musical pattern based on the alphabet and the provided melodic theme.
X:1
L:1/8
M:4/4
K:G
['G2 BG DGBG', 'cAFA dggf g2']  
X:1
L:1/8
M:4/4
K:G
|: G2 BG DGBG | G2 Bd cAFA | G2 BG DGBG | defd cAFA | G2 BG DGBG | G2 Bd cAFA | GB B2 dB B2 | 
 defd cAFA :: dggf g2 fg | adfd adfe | dggf gdfe | d2 fd cAFA | dggf g2 fa | a2 ab agfe | 
 dg g2 bg g2 | defd cAFA :|  