I was reading through Soumatome N1 Dokkai practice book when I encountered the passage below. Understanding the passage itself was not really difficult: the uncle did the prank. But when it comes to answering the multiple choice question, I was stumped. Here is how I arrived at my answer:
This can't be true.
This translates to the uncle did it.
I translated the part「叔父さんがやったのではない」as "the uncle did it"
THIS IS WHY I GOT IT WRONG
What was going on my mind was that 「いいんじゃない」 conveys roughly the same meaning as「いいんだよね」and so I applied this logic. Apparently, it's wrong.
So, is it true that 「叔父さんがやったのではない」translates to "the uncle did not do it"? And if so, if I want to convey the fact that the uncle did it using the negative, just like 「いいんじゃん」, how should I write it?