않은지

In a sentence

• 그는 아직 소식을 듣지 않은지 걱정돼요.

  He is worried whether he has not heard the news yet.

  In this sentence, '않은지' is used to express uncertainty or question about the state of not having experienced something.

• 별이 보이지 않은지 하늘이 흐려졌어요.

  The stars are not visible, suggesting that the sky has become cloudy.

  Here, '않은지' is used to denote the observation or inference regarding the absence of visibility of stars.

• 그 일이 참 오래되지 않은지 기억이 생생해.

  That event feels recent, as if not long ago, and the memory is vivid.

  In this case, '않은지' indicates a brief duration or closeness in time for the event not being far in the past.