Consider the following premises. There is at least one x_19 for which x_19 will work if and only if x_19 is a sailor. For all x_19, x_19 will write a letter if and only if x_19 will work. For all x_19, x_19 will write a letter if and only if x_19 is a lawyer. For all x_19, x_19 is not a sailor. Can we infer the following from them? For all x_19, x_19 is a lawyer.
 From the fact that there is at least one x_19 for which x_19 will work if and only if x_19 is a sailor, and that for all x_19, x_19 is not a sailor we can infer that there is at least one x_19 for which x_19 will not work. From the fact that for all x_19, x_19 will write a letter if and only if x_19 will work we can infer that for all x_19, if x_19 writes a letter, then x_19 is working. From the fact that for all x_19, if x_19 writes a letter, then x_19 is working, and that there is at least one x_19 for which x_19 will not work we can infer that there is at least one x_19 for which x_19 will not write a letter. Finally, from the fact that for all x_19, x_19 will write a letter if and only if x_19 is a lawyer, and that there is at least one x_19 for which x_19 will not write a letter we can infer that there is at least one x_19 for which x_19 is not a lawyer, which contradicts that For all x_19, x_19 is a lawyer. Therefore, the answer is no.