Consider the following premises. For all x_7, if x_7 were an office clerk, then x_7 is sleeping. For all x_7, x_7 is not a taxi driver. For all x_7, x_7 is an office clerk or x_7 will not sleep. For all x_7, if x_7 sleeps, then x_7 is a taxi driver. Can we infer the following from them? For all x_7, x_7 is not an office clerk.
 From the fact that for all x_7, x_7 is an office clerk or x_7 will not sleep we can infer that for all x_7, if x_7 sleeps, then x_7 is an office clerk. From the fact that for all x_7, if x_7 sleeps, then x_7 is a taxi driver, and that for all x_7, x_7 is not a taxi driver we can infer that for all x_7, x_7 will not sleep. From the fact that for all x_7, if x_7 were an office clerk, then x_7 is sleeping, and that for all x_7, if x_7 sleeps, then x_7 is an office clerk we can infer that for all x_7, x_7 is an office clerk if and only if x_7 will sleep. Finally, from the fact that for all x_7, x_7 is an office clerk if and only if x_7 will sleep, and that for all x_7, x_7 will not sleep we can infer that for all x_7, x_7 is not an office clerk. Therefore, the answer is yes.