어서 싸우다

go somewhere and end up fighting

싸우다 is both physically fighting and simply having a row, and -어서 supplies where or how it started: 가서 싸우다 "go there and fight", 나가서 싸우다, 와서 싸워서 "came, had a row, and then". These lines are mostly domestic — couples on holiday, friends at a concert — as in 여행 가서 싸우는 전형적인 패턴 "the classic holiday-argument pattern". The other entry 어 싸우다 covers the grander 위해 싸우다, fighting for a cause.

Register: casual spoken