Incorrect Answer.
To "decompile" the formula 
x y F(x, y)
x y M(x, y), we break it up into
significant subformulas. First, note that the binding priorities for
predicate logic suggest that this formula is written as
(x y F(x, y)) (x y M(x, y)).
- The subformula (x y F(x, y)) literally says that
'There are some x and y such that x is a father of y'. More elegantly,
we can re-express this as 'There is somebody who is a father'.
- The subformula
x y M(x, y)
litteraly says that 'There are some x and y such that x is a mother of y'. More elegantly,
we can re-express this as 'There is somebody who is a mother'.
- The entire formula therefore says 'If there exists any father, then there are no mothers'.
Evidently, this is not the sentence we sought to express.
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