Translate the following inference to logic notation: For all x, x_6 will sleep or x_6 is not a soldier. There is at least one x for which if x_6 reads a book, then x_6 is a soldier. For all x, if x_6 sleeps, then x_6 is reading a book. Therefore there is at least one x for which x_6 is a soldier if and only if x_6 will read a book.
forall x: P(x) or ~Q(x). exists x: R(x) -> Q(x). forall x: P(x) -> R(x). Therefore exists x: Q(x) <-> R(x).