by
US /baɪ/
UK /baɪ/

1.
~으로, ~에 의해
indicating the means of achieving something
:
•
He traveled by train.
그는 기차로 여행했다.
•
She learned English by watching movies.
그녀는 영화를 보면서 영어를 배웠다.
2.
~에 의해
indicating the agent performing an action in a passive sentence
:
•
The book was written by a famous author.
그 책은 유명한 작가에 의해 쓰여졌다.
•
The ball was hit by the player.
공은 선수에 의해 쳐졌다.
3.
4.
~까지
indicating a deadline or a point in time before which something happens
:
•
Please submit your report by Friday.
금요일까지 보고서를 제출해 주세요.
•
I need to finish this by noon.
정오까지 이걸 끝내야 해.