To be worried or troubled; an intransitive verb expressing being mentally distressed or puzzled by problems or choices.
将来の仕事について毎日悩んでいる。
I'm worrying every day about my future job.
彼女は人間関係のことで深く悩んでいるようだ。
She seems to be deeply troubled about her interpersonal relationships.
症状が良くならないので医者は悩んでいた。
The doctor was puzzled because the symptoms weren't improving.