This is the 5615th most frequent Korean word.
믿어야
"믿어야" means "must believe" or "should believe."
믿다 is used here in a combined form with 어야, indicating a necessity or obligation.
친구를 끝까지 믿어야 서로의 우정을 지킬 수 있어요.
We must trust our friends to the end to preserve our friendship.
믿다 is indicating trusting or believing in personal qualities.
이 상황에서는 자신의 능력을 믿어야 해요.
In this situation, you must trust your abilities.
믿다 is used to suggest having faith or confidence in changes.