ねばならない/ねばならぬ/ねば => have to do; must; should ~ N2
ね => isn't it? right? eh? N5
じゃありません => not to be N5
Emphasize negative meaning
かねない => Afraid that N2
Potential, Possibility
ね => Requests confirmation from the listener N5
Particles
かねる => unable to do something; can’t do something N2
ねばならない => Must A N2
Needs, Requirements
じゃありませんでした => was not, were not N5
Emphasize negative meaning
かねない => (someone) might do something; something might happen N2
そうじゃありません => Not like that, Not that way N5
Confirm
[兼「か」]ねて => Also for the purpose of A N1
Miscellaneous
お…ねがう => please do; could you please…; I ask of you to ~ N4
Respectful, humble