Consider the following premises. There is at least one x for which if x were an office clerk, then x is a nurse. For all x, x is a bartender or x is a nurse. For all x, x is not a bartender. For all x, if x were a nurse, then x is an office clerk. Can we infer the following from them? There is at least one x for which x is an office clerk.
 From the fact that for all x, if x were a nurse, then x is an office clerk, and that there is at least one x for which if x were an office clerk, then x is a nurse we can infer that there is at least one x for which x is a nurse if and only if x is an office clerk. From the fact that there is at least one x for which x is a nurse if and only if x is an office clerk we can infer that there is at least one x for which if x were a nurse, then x is an office clerk. From the fact that for all x, x is a bartender or x is a nurse, and that for all x, x is not a bartender we can infer that for all x, x is a nurse. Finally, from the fact that there is at least one x for which if x were a nurse, then x is an office clerk, and that for all x, x is a nurse we can infer that there is at least one x for which x is an office clerk. Therefore, the answer is yes.