Consider the following premises. For all z, z will drive a car if and only if z will write a letter. For all z, z will write a letter if and only if z will take a plane. For all z, z will not drive a car. Can we infer the following from them? There is at least one z for which z will take a plane.
 From the fact that for all z, z will write a letter if and only if z will take a plane we can infer that for all z, if z takes a plane, then z is writing a letter. From the fact that for all z, z will drive a car if and only if z will write a letter, and that for all z, z will not drive a car we can infer that for all z, z will not write a letter. Finally, from the fact that for all z, if z takes a plane, then z is writing a letter, and that for all z, z will not write a letter we can infer that for all z, z will not take a plane, which contradicts that There is at least one z for which z will take a plane. Therefore, the answer is no.