Consider the following premises. For all x, if x climbs a mountain, then x is reading a book. For all x, if x reads a book, then x is a soldier. For all x, if x drinks water, then x is climbing a mountain. For all x, x will drink water. There is at least one x for which x is a scientist. Can we infer the following from them? If we can, name the inference rule being used: Some soldiers are scientists.
 From the fact that for all x, if x drinks water, then x is climbing a mountain, and that for all x, if x climbs a mountain, then x is reading a book we can infer that for all x, if x drinks water, then x is reading a book via universal transitivity. From the fact that for all x, if x drinks water, then x is reading a book, and that for all x, x will drink water we can infer that for all x, x will read a book via universal modus ponens. From the fact that for all x, if x reads a book, then x is a soldier, and that for all x, x will read a book we can infer that for all x, x is a soldier via universal modus ponens. Finally, from the fact that for all x, x is a soldier, and that there is at least one x for which x is a scientist we can infer that some soldiers are scientists via existential conjunction. Therefore, the answer is yes.