Consider the following premises. For all x_11, x_11 will take a plane or x_11 is not a police officer. For all x_11, x_11 is not a carpenter. There is at least one x_11 for which x_11 is a police officer or x_11 will play squash. For all x_11, x_11 is a carpenter if and only if x_11 will take a plane. Can we infer the following from them? For all x_11, x_11 will not play squash.
 From the fact that for all x_11, x_11 is a carpenter if and only if x_11 will take a plane, and that for all x_11, x_11 is not a carpenter we can infer that for all x_11, x_11 will not take a plane. From the fact that for all x_11, x_11 will take a plane or x_11 is not a police officer we can infer that for all x_11, if x_11 were a police officer, then x_11 is taking a plane. From the fact that for all x_11, if x_11 were a police officer, then x_11 is taking a plane, and that for all x_11, x_11 will not take a plane we can infer that for all x_11, x_11 is not a police officer. Finally, from the fact that there is at least one x_11 for which x_11 is a police officer or x_11 will play squash, and that for all x_11, x_11 is not a police officer we can infer that there is at least one x_11 for which x_11 will play squash, which contradicts that For all x_11, x_11 will not play squash. Therefore, the answer is no.