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There are at least two squares:

\hspace{5mm} ∃x ∃y ( Square(x) ∧ Square(y) ∧ ¬x=y )

At least two squares are broken:

\hspace{5mm} ∃x ∃y (

\hspace{10mm} Square(x) ∧ Broken(x)

\hspace{10mm} ∧

\hspace{10mm} Square(y) ∧ Broken(y)

\hspace{10mm} ∧

\hspace{10mm} ¬x=y

\hspace{5mm} )

There are at least three squares:

\hspace{5mm} ∃x ∃y ∃z (

\hspace{10mm} Square(x) ∧ Square(y) ∧ Square(z)

\hspace{10mm} ∧

\hspace{10mm} ¬x=y ∧ ¬y=z ∧ ¬x=z

\hspace{5mm} )

There are at most two squares:

\hspace{5mm} ¬There are at least three squares

\hspace{5mm} ¬∃x ∃y ∃z ( Square(x) ∧ Square(y) ∧ Square(z) ∧ ¬x=y ∧ ¬y=z ∧ ¬x=z)

There are exactly two squares:

\hspace{5mm} There are at most two squares ∧ There are at least two squares

\textbf{Number: alternatives}

There is at most one square:

\hspace{5mm} ∀x ∀y ( (Square(x) ∧ Square(y)) → x=y )

There are at most two squares:

\hspace{5mm} ∀x ∀y ∀z (

\hspace{10mm} (Square(x) ∧ Square(y) ∧ Square(z))

\hspace{10mm} →

\hspace{10mm} (x=y ∨ y=z ∨ x=z)

\hspace{5mm} )

There is exactly one square:

\hspace{5mm} ∃x ( Square(x) ∧ ∀y( Square(y) → x=y ) )

There are exactly two squares:

\hspace{5mm} ∃x∃y (

\hspace{10mm} Square(x) ∧ Square(y) ∧ ¬x=y

\hspace{10mm} ∧

\hspace{10mm} ∀z( Square(z) → (z=x ∨ z=y) )

\hspace{5mm} )

14.2--14.3

14.4--14.5

14.10--14.11