I’m struggling to understand an example sentence from Tae Kim’s guide.The sentence is the following:
先生だと、きっと年上なんじゃないですか。And is translated to: If he’s a teacher, he must be older for sure right?
now presumably なんじゃない is just なのじゃない。What I am failing to understand is why the の is conjugated to it’s negative form. My literal of reading this would go something like: if he’s a teacher, for sure not the event of being older right? Basically the opposite meaning. Why am I wrong?