Consider the following premises. For all x_8, x_8 will play tennis or x_8 will take a plane. There is at least one x_8 for which x_8 is not a soldier. For all x_8, x_8 is a soldier if and only if x_8 will take a plane. For all x_8, x_8 will not play tennis or x_8 will write a letter. Can we infer the following from them? There is at least one x_8 for which x_8 will write a letter.
 From the fact that for all x_8, x_8 is a soldier if and only if x_8 will take a plane, and that there is at least one x_8 for which x_8 is not a soldier we can infer that there is at least one x_8 for which x_8 will not take a plane. From the fact that for all x_8, x_8 will play tennis or x_8 will take a plane, and that for all x_8, x_8 will not play tennis or x_8 will write a letter we can infer that for all x_8, x_8 will take a plane or x_8 will write a letter. Finally, from the fact that for all x_8, x_8 will take a plane or x_8 will write a letter, and that there is at least one x_8 for which x_8 will not take a plane we can infer that there is at least one x_8 for which x_8 will write a letter. Therefore, the answer is yes.