Let’s learn about "안 자다 / 못 자다”

* 잘 못 잤어요 : I can’t sleep because it is so hot.

* 나는 어제 밤에 안 잤다 : I didn't sleep last night.

* 어제밤에 밤새 깨 있었다 : I was up all night last night.

1) 안 자다 : I am awake by my will

2) 못 자다 : I can’t sleep because other make me not sleep