Formulate a musical piece by utilizing the specified motif and alphabet-based structure.
X:1
L:1/8
M:4/4
K:Emin
['GA B2', 'G2 G2']  
X:1
L:1/8
M:4/4
K:Emin
 E3 F GA B2 | c2 BA B2 AG | A2 DD D2 EF | GA B2 A3 G | G8 :| B2 AG A2 GF | G2 FE F4 | G2 G2 A2 B2 | 
 c2 BA B2 EE | E6 ^c^d | e6 EF | G2 G2 F3 E | E8 ||  