Consider the following premises. For all y, y will drive a car if and only if y will write a letter. For all y, if y plays a game, then y is driving a car. For all y, y is an office clerk or y will cook. There is at least one y for which if y were an office clerk, then y is writing a letter. For all y, if y cooks, then y is playing a game. Can we infer the following from them? For all y, y will not drive a car.
 From the fact that for all y, y will drive a car if and only if y will write a letter we can infer that for all y, if y writes a letter, then y is driving a car. From the fact that for all y, if y cooks, then y is playing a game, and that for all y, if y plays a game, then y is driving a car we can infer that for all y, if y cooks, then y is driving a car. From the fact that there is at least one y for which if y were an office clerk, then y is writing a letter, and that for all y, if y writes a letter, then y is driving a car we can infer that there is at least one y for which if y were an office clerk, then y is driving a car. Finally, from the fact that there is at least one y for which if y were an office clerk, then y is driving a car, that for all y, if y cooks, then y is driving a car, and that for all y, y is an office clerk or y will cook we can infer that there is at least one y for which y will drive a car, which contradicts that For all y, y will not drive a car. Therefore, the answer is no.