Okay, the user wants me to translate "vice-regent" into Japanese. Let me think about the correct term.
First, "vice-regent" is a title, often used in historical or formal contexts. In Japanese, the equivalent would probably be "副王" (fuku-ō), which literally means "vice king." But I should check if there's a more standard translation.
Wait, sometimes "vice-regent" can also be translated as "代理王" (dai-ryō), which means "regent" or "proxy king." However, "副王" is more commonly used in historical contexts, like in the Qing Dynasty's governance over territories like Taiwan.
I should also consider if there's a specific term used in modern Japanese. Maybe "副総督" (fuku-sōtoku) for "vice governor," but that's more for governors. Since "vice-regent" is a regent, "副王" seems accurate.
Let me confirm with some references. In Japanese history, the term "副王" is used for positions like the Viceroy of the Qing Dynasty. So, "副王" is the right translation here. I'll go with that.