Compose a musical piece using the designated musical pattern's alphabetic representation and the assigned melodic theme.
X:1
L:1/8
Q:1/2=80
M:2/2
K:G
['A BGGB dcdf AFcA cFFA BGGB dcdg']  
X:1
L:1/8
Q:1/2=80
M:2/2
K:G
 A | BGGB dcdf | AFcA cFFA | BGGB dcdg | fdcA G3 |:  