Negative questions : Normal Vs Explanation seeking


I'm pretty sure this question is basic and may be a duplicate to any existing
ones.

> 授業があるんじゃない?
>
> 授業がない?

  1. Isn't there a class?
  2. There is no class?

Seems similar to me.




授業があるんじゃない？ This would be said by your roomate who knows for sure that you
have a class that given day, to you, who are still in your pajamas despite the
class starting soon. (This ん is tricky. If you simply asked 授業があるの？then such
nuance would not be included, and it would be a simple question: "Do we have a
class today?"). Therefore the above could be translated as, "You do have a
class today, right?".

授業がない？ This is just a simple question. You came to the classroom late, yet the
teacher has not arrived yet. You ask one of the classmates, "(So) there is no
class?".




授業があるんじゃない？ This would be said by your roomate who knows for sure that you
have a class that given day, to you, who are still in your pajamas despite the
class starting soon. (This ん is tricky. If you simply asked 授業があるの？then such
nuance would not be included, and it would be a simple question: "Do we have a
class today?"). Therefore the above could be translated as, "You do have a
class today, right?".

授業がない？ This is just a simple question. You came to the classroom late, yet the
teacher has not arrived yet. You ask one of the classmates, "(So) there is no
class?".

