Consider the following premises. For all x_3, if x_3 were a janitor, then x_3 is sad. For all x_3, if x_3 drinks water, then x_3 is a janitor. There is at least one x_3 for which x_3 will drink water. Can we infer the following from them? There is at least one x_3 for which x_3 is sad.
 From the fact that for all x_3, if x_3 drinks water, then x_3 is a janitor, and that there is at least one x_3 for which x_3 will drink water we can infer that there is at least one x_3 for which x_3 is a janitor. Finally, from the fact that for all x_3, if x_3 were a janitor, then x_3 is sad, and that there is at least one x_3 for which x_3 is a janitor we can infer that there is at least one x_3 for which x_3 is sad. Therefore, the answer is yes.