Craft a musical work adhering to the specified theme and structure.
X:1
L:1/4
Q:1/2=100
M:2/2
K:F
['f/g/ a f']  
X:1
L:1/4
Q:1/2=100
M:2/2
K:F
 f/g/ | a f c f | f2 A2 | B/c/d/B/ G/A/B/G/ | A/B/A/G/ F f/g/ | a f b a | g2 f2 | e/f/ g G =B | 
 c3 |:  