Consider the following premises. For all x_3, if x_3 were a doctor, then x_3 is not a server. For all x_3, if x_3 were a poet, then x_3 is a server. There is at least one x_3 for which x_3 is a poet. Can we infer the following from them? There is at least one x_3 for which x_3 is not a doctor.
 From the fact that for all x_3, if x_3 were a poet, then x_3 is a server, and that there is at least one x_3 for which x_3 is a poet we can infer that there is at least one x_3 for which x_3 is a server. Finally, from the fact that for all x_3, if x_3 were a doctor, then x_3 is not a server, and that there is at least one x_3 for which x_3 is a server we can infer that there is at least one x_3 for which x_3 is not a doctor. Therefore, the answer is yes.