1.know: 사실, 정보를 알고 있는 상태. I know the way there. I don't know why there are so many people there. Everyone doesn't know what is important tings. 2.understand: 이해하다지만 알다로도 많이 쓰임. I understand how you feel. I uderstand why you did that but I don't agree with your decision. I don't understand it. 3.find out: 몰랐던 사실, 정보를 알게되다. 그 과정, 변화를 이야기함. I found out about that just yesterday. - just yesterday: 어..