If someone such as a lawyer or a politician represents a person, a group of people, or a place, they act on behalf of that person, group, or place. 代表; 代理
If you represent a person or group at an official event, you go there on their behalf. 代表 (出席) The general secretary may represent the president at official ceremonies. 秘书长可以在官方仪式上代表主席。