禁止形 => Negative imperative form N4
[禁止「きんし」] => Don't do N4
Can, Should, Must
命令形 => Imperative form N4
[命令「めいれい」] => Do A (command) N4
Can, Should, Must
~をきんじえない(~を禁じ得ない) => can't help but; can't refrain from ~ N1
を[禁「きん」]じ[得「え」]ない => Can't help but do A, can't hold back from A (emotional response to something) N1
Will, Decision, Doing