禁止形 => Negative imperative form N4
[禁止「きんし」] => Don't do N4
Can, Should, Must
なくて済む/ないで済む => get by without doing ~ N2
まだV-られない => Not yet ~ N4
Ability
に[難「むずか」]くない => It's not hard to A N1
Adjectival, Descriptions
ままになる => Just let... N4
Continuous
ずに済む => get by without doing ~ N2
~ないではすまない / ずにはすまない      => must; will definitely; can't help but to ~ N1
ずにはすまない/ないではすまない => A must be done N1
Potential, Possibility
いまごろになって => Only now ... N3
Time
抜きに...れない => without; leaving out; cutting out ~ N2
Conditions (necessary conditions)
むりに => Try to..., make an effort to... N3
Necessity, obligation