I’m still on the very first lesson, don’t worry about me.

But I just literally understood it like… cause one of the things was to translate “It is cool!” and I was like… well it can be 대박입니다 or 멋있습니다  but wHY? Why isn’t it 대박있습니다 or 멋입니다 and then I got it that 대박 already means “cool” and is an adjective (I think) and you only have to add 이다” to make it mean something is something whereas 멋 is one of those nouns (I think) that you have to pair with “있다” and it makes it mean something is something.