元首
Head of state is the highest-ranking constitutional position in a sovereign state. A head of state has some or all of the roles listed below, often depending on the constitutional category (above), and does not necessarily regularly exercise the most power or influence of governance. There is usually a formal public ceremony when a person becomes head of state, or some time after. This may be the swearing in at the inauguration of a president of a republic, or the coronation of a monarch.