Develop a musical composition based on the provided pattern of letters and incorporating the given motif within it.
X:1
L:1/4
M:4/4
K:F
['A B']  
X:1
L:1/4
M:4/4
K:F
 C | F G A B | c2 B A | G F E F | G3 | A | B A B G | B A G F | E F G A | G3 | C | F G A B | 
 c2 B A | d B A G | (F E) D | C | F G A F | E D z D/D/ | G A B G | F E z | E/E/ | A B c A | 
 G F z d | c A B G | F3 ||  