誰

誰 is the basic question word meaning 'who' used to ask about a person. In everyday Japanese, 誰 is often followed by a verb or used with ですか to form a simple question. The particle after 誰 depends on what you are asking about (subjectはが, objectをを, etc.). In many cases, you can just place 誰 before ですか to ask who someone is, or use 誰が/誰を with a verb to specify what action is performed by or to that person.