활동을

activity

→ 활동
phrase Rare #22,867
activity 활동 means “activity” or “activities”; 을 marks it as the object of the verb and usually has no direct English equivalent.
KO: 저는 주말마다 야외 활동을 즐겨요.
EN: I enjoy outdoor activities every weekend.

근데 언제쯤 이 뱀이 활동을 시작할까요?

But when will this snake become active?

— 제5원소 (1997)

빈센트는 정치 활동을 해 보겠다고 했다.

Vincent said he was going to try his hand at politics.

영상 확인 결과 검은 행성이 활동을 멈췄습니다

After reviewing the footage, we confirmed that the black planet had ceased its activity.

— 제5원소 (1997)