\begin{frame}
  \frametitle{Exercises}
  
  Meaning of the symbols:
  \begin{talign}
    a: \quad& \text{Alice} &
    L(x,y): \quad & \text{$x$ likes $y$}
  \end{talign}
  Translate the following sentences into predicate logic:
  \bigskip
  
  \begin{alertblock}{}
    Everybody who likes someone, also likes Alice.
  \end{alertblock}
  \pause
  \begin{exampleblock}{}
    \vspace{-1.5ex}
    \begin{talign}
      \myall{x}{\big(\; \myex{y}{L(x,y)} \to L(x,a) \;\big)}
    \end{talign}
  \end{exampleblock}
  \pause\bigskip\bigskip
  
  The brackets are important. A typical \aemph{mistake} in the exam:
  \begin{talign}
    \myall{x}{\myex{y}{\big(\; L(x,y) \to L(x,a) \;\big)}}
  \end{talign}%
  \pause\vspace{-2ex}
  \begin{alertblock}{}
    What does this formula mean?
  \end{alertblock}
  \vspace{10cm}
\end{frame}