Translate the following inference to logic notation: For all x, if x_14 were a taxi driver, then x_14 is happy. William is driving a car if and only if it is sunny. It is not sunny. Mary is not happy. Therefore William is not driving a car and Mary is not a taxi driver.
forall x: P(x) -> Q(x). p <-> q. ~q. ~Q(a). Therefore ~p and ~P(a).