This is the 17230th most frequent Korean word.
서울시장과
"서울시장과" means "with the mayor of Seoul" in English.
서울시장과 is used here to indicate 'with the Seoul mayor', showing accompaniment.
서울시장과 함께 도시 발전 계획을 논의했습니다.
We discussed the city's development plans with the mayor of Seoul.
서울시장과의 refers to 'with the Seoul mayor' in the sense of a possessive relation, often used to describe a meeting or other event involvement.
서울시장과의 미팅은 다음 주 금요일로 예정되어 있습니다.
The meeting with the mayor of Seoul is scheduled for next Friday.
서울시장과도 uses the suffix -도 to add 'also', indicating an additional subject with whom the acquaintance exists.