Consider the following premises. For all y, y will sleep or y is not a mechanic. There is at least one y for which y will drink water or y is a mechanic. For all y, y will sleep or y will not drink water. Can we infer the following from them? For all y, y will not sleep.
 From the fact that for all y, y will sleep or y is not a mechanic we can infer that for all y, if y were a mechanic, then y is sleeping. From the fact that for all y, y will sleep or y will not drink water we can infer that for all y, if y drinks water, then y is sleeping. Finally, from the fact that for all y, if y drinks water, then y is sleeping, that for all y, if y were a mechanic, then y is sleeping, and that there is at least one y for which y will drink water or y is a mechanic we can infer that there is at least one y for which y will sleep, which contradicts that For all y, y will not sleep. Therefore, the answer is no.