I have recently reached the の particle in my grammar book and it really confused me.
Question #1: When we attach の to a verb clause like this,
毎日勉強するの大変
does it mean I'm talking about the act of studying everyday and that it classifies as hard, and if so, can this form only be used for dictionary form verbs?
Question #2 : When I'm using の for explanation. This sentence was present in my book:
その人が買うんじゃなかったの?
First of all, why is there another の at the end of the sentence? Isn't it already conjugated as ん? The main question here is: what is the difference between that sentence and this one?
それ人が買ったんじゃない?
If I got it wrong and they're not different could someone tell me what they mean? I know I'm asking a lot and I'm really sorry for that, but both questions got me confused. I'd appreciate any help.