Consider the following premises. If it is late, then John is drinking water. If John were a doctor, then it is late. For all x_10, x_10 will drink water or x_10 is a doctor. If John drinks water, then it is late. Can we infer the following from them? It is late.
 From the fact that for all x_10, x_10 will drink water or x_10 is a doctor we can infer that John is drinking water or John is a doctor. From the fact that if John drinks water, then it is late, and that if it is late, then John is drinking water we can infer that John is drinking water if and only if it is late. From the fact that John is drinking water if and only if it is late we can infer that if John drinks water, then it is late. Finally, from the fact that if John drinks water, then it is late, that if John were a doctor, then it is late, and that John is drinking water or John is a doctor we can infer that it is late. Therefore, the answer is yes.