Consider the following premises. For all x_5, x_5 will write a letter and x_5 is poor. For all x_5, if x_5 writes a letter, then x_5 is playing tennis. There is at least one x_5 for which if x_5 takes a plane, then x_5 is playing tennis. Can we infer the following from them? For all x_5, x_5 will not play tennis.
 From the fact that for all x_5, x_5 will write a letter and x_5 is poor we can infer that for all x_5, x_5 will write a letter. From the fact that for all x_5, x_5 will write a letter we can infer that for all x_5, x_5 will write a letter or x_5 will take a plane. Finally, from the fact that for all x_5, if x_5 writes a letter, then x_5 is playing tennis, that there is at least one x_5 for which if x_5 takes a plane, then x_5 is playing tennis, and that for all x_5, x_5 will write a letter or x_5 will take a plane we can infer that there is at least one x_5 for which x_5 will play tennis, which contradicts that For all x_5, x_5 will not play tennis. Therefore, the answer is no.