忙しくないさま
to be unbusy
忙しくありません。
I am not that busy.
忙しくないこと
the condition of not being busy
I am not busy.
I am sorry to stand in your way.
忙しくて行けないんだ。
Please pardon me interrupting you.
I am sorry to make such a claim on your friendship―presume so far on your friendship.
Pardon me for interrupting you.