Develop a musical composition based on the provided pattern of letters and incorporating the given motif within it.
X:1
L:1/8
M:2/4
K:E
['B2 =GF E2']  
X:1
L:1/8
M:2/4
K:E
 =G | =G3 =DGBA=c | B6 =GA | B2 B2 B2 A=G | F6 B2 | =GAB=c B2 AG | F=G A2 | =GAB=c | B2 =GF | 
 E2 BA | B2 =GF | E2 z |]  