This is the 270th most frequent Korean word.
일을
"일을" means "work" or "task" (object form).
Here, '일을' means 'the work' as the object of the verb '끝냈어' (finished).
나는 일을 끝냈어.
I finished the work.
In this sentence, '일을' refers to 'the work' or 'what one does,' emphasizing the action of working hard.
그는 항상 일을 열심히 해.
He always works hard.
The phrase '일을 구하다' means 'to get a job,' where '일을' specifies the type of task someone is seeking.