Japanese Grammar for Obligation ~nakute wa ikenai/naranai/dame (~なくてはいけない/ならない/だめ)

Hello, we meet again, with me riizhu^^, let's learn Japanese language online, we learned prohibition grammar in Japanese yesterday, and today we are going to learn a grammar for obligation in Japanese language. Maybe some of learners think to make an obligation just change the negative to positive, isn't it? but, in Japanese we will involve double negatives which create an affirmative meaning.