~じゃ(では)あるまいし => isn't it; I wonder if it's not ~ N1
Invite and advise
じゃ(あ) / では => Then, so (Expressing attitude) N5
Change the way you speak
じゃありませんでした => was not, were not N5
Emphasize negative meaning
じゃないか => right? isn't it? let's~; confirmation N4
Speculation
じゃありません => not to be N5
Emphasize negative meaning
じゃ(あ) / では => then; well; so; well then N5
Change the way you speak
じゃないか / ではないか => right? isn't it? N3
Confirm
んじゃないか => right? isn't it? let's~; confirmation N4
Confirm
じゃないか / ではないか => right?; isn't it? (Criticism) N3
Criticize
んじゃなかったか => shouldn't have... N4
Regret
じゃないか / ではないか => right? isn't it? let's~; confirmation N3
Surprised
じゃ(あ) / では => If so, Well (then), In that case N5
Speculation