\item \self Given is the following formula in predicate logic
$$\phi = \exists x \forall y \Bigl(
\bigl(
P(x,y) \implies Q(x,y)
\bigr)
\vee
\bigl(
P(y, x)  \implies R(x,y)
\bigr)
\Bigr). $$
Draw the syntax tree for $\phi$.