This is the 15106th most frequent Korean word.
발해를
"발해를" is a form of "발해," referring to Balhae, an ancient Korean kingdom.
Here, '발해를' refers to the Balhae Kingdom being studied.
그는 발해를 연구하는 역사 학자입니다.
He is a historian who studies Balhae.
In this sentence, '발해를' signifies the Balhae region that is being traveled.
우리는 발해를 여행하며 아름다운 풍경을 만끽했습니다.
We traveled through Balhae and enjoyed the beautiful scenery.
Here, '발해를' indicates Balhae as the subject of the project.