Translate the following inference to logic notation: There is at least one x for which if x_6 plays tennis, then x_6 is running. For all x, x_6 will play tennis. For all x, x_6 will go running if and only if x_6 will read a book. Therefore there is at least one x for which x_6 will go running.
exists x: P(x) -> Q(x). forall x: P(x). forall x: Q(x) <-> R(x). Therefore exists x: Q(x).