Is a mayor in charge of a city or a country?
The mayor of a town or city is the person who has been elected for a fixed period of time to run its government. 市长
in charge of
The president of a country that has no king or queen is the person who is the head of state of that country. 总统
In many countries, a mayor is the highest-ranking official in a municipal government such as that of a city or a town.
Worldwide, there is a wide variance in local laws and customs regarding the powers and responsibilities of a mayor as well as the means by which a mayor is elected or otherwise mandated.