불면증

In a sentence

• 나는 불면증 때문에 매일 잠이 부족하다.

  I lack sleep every day because of insomnia.

  Here, '불면증' is used as the subject causing the effect (lack of sleep).

• 불면증을 극복하려고 노력하고 있어요.

  I am trying to overcome insomnia.

  Here, '불면증' is the object of the action (overcoming).

• 불면증은 건강에 해로운 영향을 줄 수 있다.

  Insomnia can have detrimental effects on health.

  Here, '불면증' serves as a general topic or subject being discussed.