Consider the following premises. For all z_1, if z_1 plays tennis, then z_1 is an electrician. There is at least one z_1 for which z_1 will play tennis. For all z_1, if z_1 were an electrician, then z_1 is running. Can we infer the following from them? If we can, name the inference rule being used: There is at least one z_1 for which z_1 will go running.
 From the fact that for all z_1, if z_1 plays tennis, then z_1 is an electrician, and that there is at least one z_1 for which z_1 will play tennis we can infer that there is at least one z_1 for which z_1 is an electrician via existential modus ponens. Finally, from the fact that for all z_1, if z_1 were an electrician, then z_1 is running, and that there is at least one z_1 for which z_1 is an electrician we can infer that there is at least one z_1 for which z_1 will go running via existential modus ponens. Therefore, the answer is yes.