Consider the following premises. For all z_1, if z_1 were a lawyer, then z_1 is not a doctor. Some doctors will listen to a song. Can we infer the following from them? For all z_1, z_1 is a lawyer.
 From the fact that some doctors will listen to a song we can infer that there is at least one z_1 for which z_1 is a doctor. Finally, from the fact that for all z_1, if z_1 were a lawyer, then z_1 is not a doctor, and that there is at least one z_1 for which z_1 is a doctor we can infer that there is at least one z_1 for which z_1 is not a lawyer, which contradicts that For all z_1, z_1 is a lawyer. Therefore, the answer is no.