Consider the following premises. For all x_8, x_8 is a janitor if and only if x_8 will take a plane. There is at least one x_8 for which x_8 will play tennis if and only if x_8 will take a plane. For all x_8, x_8 is not a janitor. Can we infer the following from them? There is at least one x_8 for which x_8 will not play tennis.
 From the fact that for all x_8, x_8 is a janitor if and only if x_8 will take a plane we can infer that for all x_8, if x_8 takes a plane, then x_8 is a janitor. From the fact that for all x_8, if x_8 takes a plane, then x_8 is a janitor, and that for all x_8, x_8 is not a janitor we can infer that for all x_8, x_8 will not take a plane. Finally, from the fact that there is at least one x_8 for which x_8 will play tennis if and only if x_8 will take a plane, and that for all x_8, x_8 will not take a plane we can infer that there is at least one x_8 for which x_8 will not play tennis. Therefore, the answer is yes.