の and か question forms　feedback Could someone please check if I got these sentences correct? Do they sound natural? Just playing around with sentences :) 1. その人が買うんじゃなかったの？ Wasn't that person going to buy? 2. その人が買わなかったの？ Wasn't that person buying? 3. その人が買ったかどうか知らなかったの？ Didn't you know whether that person bought or not? 4. その人が買うんだったか知らなかったの？ Didn't you know that person was going to buy? 5. その人が買うのを知らないの？ Don't you know that person is going to buy? 6. その人が買わないんじゃない？ Isn't it that that person isn't going to buy? 7.その人が買ったのか、誰か知らないの？ Doesn't anybody know that person bought it?　 8.その人が買ったか、だれか知らないの？ Doesn't anybody know that person bought? Help much appreciated! ありがとうございます！