Consider the following premises. For all x_8, x_8 will take a plane or x_8 will not sleep. For all x_8, if x_8 takes a plane, then x_8 is not a doctor. There is at least one x_8 for which x_8 is a doctor. Can we infer the following from them? There is at least one x_8 for which x_8 will not sleep.
 From the fact that for all x_8, if x_8 takes a plane, then x_8 is not a doctor, and that there is at least one x_8 for which x_8 is a doctor 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 take a plane or x_8 will not sleep we can infer that for all x_8, if x_8 sleeps, then x_8 is taking a plane. Finally, from the fact that for all x_8, if x_8 sleeps, then x_8 is taking a plane, 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 not sleep. Therefore, the answer is yes.