Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/4
M:3/2
K:F
['F3/2 G/ F f2 A', 'G/F/ G2']  
X:1
L:1/4
M:3/2
K:F
|: F3/2 G/ F f2 A | c2 a g e c | F3/2 G/ F f2 A | G2 (A/G/) (A/G/) D E :: F3/2 G/ F f2 f | 
 f (g/f/)(e/d/) e2 g | (g e) g g e f | g f e d2 c | f a g a f A | c A G/F/ G2 F/>D/ | F2 f c G/F/ | 
 G2 (A/<G/) G D E | !fermata!F3 |]  