How can I say "Trying to keep a habit is really hard" in Korean?
I'm trying to make sentence using -(ㄴ/는) 다는 것, but if there's any other ways to say it without using this conjugation please let me know.
Those might be common way of same meaning.
습관으로 만들기 어려워.
And it's a bit unnatural but it's the translation of your sentence.
버릇을 지키는 것은 어려워.
It's not a idiom but sometimes people try other sentences and they are the natural way.
'My mom is rock.' It doesn't mean that she's a hard stone of mountain. Right?
Hope this answer will help you.