Consider the following premises. There is at least one y for which y will make tea or y is not a bartender. For all y, y is a bartender or y will not make tea. Can we infer the following from them? If we can, name the inference rule being used: There is at least one y for which if y were a bartender, then y is making tea.
We can infer this via the existential rewriting rule. Therefore, the answer is yes.