Consider the following premises. For all x_11, x_11 is a sailor or x_11 is not happy. There is at least one x_11 for which x_11 will work or x_11 is happy. For all x_11, x_11 will not work. Can we infer the following from them? For all x_11, x_11 is not a sailor.
 From the fact that for all x_11, x_11 is a sailor or x_11 is not happy we can infer that for all x_11, if x_11 were happy, then x_11 is a sailor. From the fact that there is at least one x_11 for which x_11 will work or x_11 is happy, and that for all x_11, x_11 will not work we can infer that there is at least one x_11 for which x_11 is happy. Finally, from the fact that for all x_11, if x_11 were happy, then x_11 is a sailor, and that there is at least one x_11 for which x_11 is happy we can infer that there is at least one x_11 for which x_11 is a sailor, which contradicts that For all x_11, x_11 is not a sailor. Therefore, the answer is no.