Consider the following premises. For all x_9, x_9 is a nurse if and only if x_9 will play tennis. For all x_9, x_9 is a nurse if and only if x_9 will play tennis. Can we infer the following from them? For all x_9, if x_9 were a nurse, then x_9 is playing tennis.
 From the fact that for all x_9, x_9 is a nurse if and only if x_9 will play tennis we can infer that for all x_9, if x_9 plays tennis, then x_9 is a nurse. Finally, from the fact that for all x_9, x_9 is a nurse if and only if x_9 will play tennis we can infer that for all x_9, if x_9 were a nurse, then x_9 is playing tennis. Therefore, the answer is yes.