Consider the following premises. For all x_13, x_13 will work. For all x_13, x_13 will drive a car or x_13 will play a game. For all x_13, x_13 will not drive a car or x_13 is sad. There is at least one x_13 for which x_13 will not play a game. Can we infer the following from them? For all x_13, x_13 is not sad.
 From the fact that for all x_13, x_13 will drive a car or x_13 will play a game, and that for all x_13, x_13 will not drive a car or x_13 is sad we can infer that for all x_13, x_13 will play a game or x_13 is sad. From the fact that for all x_13, x_13 will play a game or x_13 is sad, and that there is at least one x_13 for which x_13 will not play a game we can infer that there is at least one x_13 for which x_13 is sad. From the fact that for all x_13, x_13 will work, and that there is at least one x_13 for which x_13 is sad we can infer that there is at least one x_13 for which x_13 will work and x_13 is sad. Finally, from the fact that there is at least one x_13 for which x_13 will work and x_13 is sad we can infer that there is at least one x_13 for which x_13 will work, which contradicts that For all x_13, x_13 is not sad. Therefore, the answer is no.