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:F
['GABG ABcA defd cAFA', 'BABG A2 D2 BABG']  
X:1
L:1/8
M:4/4
K:F
 GABG ABcA | defd cAFA | B2 g>B A2 f>A | G2 B>G FEFD | GABG ABcA | defd cAFA | BABG DGFA | 
 G2 G>F G4 :: gfga g2 d2 | gfga g3 d | fefg fagf | e2 c>d c3 A | BABG A2 D2 | BABG A2 D2 | 
 BABG DGFA | G2 G>F G4 :|  