めったにない => Rarely N3
Degree. Level, Amount
といったらない/といったらありはしない => Extremely A, Very A, A beyond description N1
Degree/ Level/Amount
にはあたらない => There's no need to A, N1
Need/Requirements
といえば/というと/といったら => N3
Considering, Concerning
にほかならない => Only A N2
Reason, Result, Response
に[沿「そ」]って/に[沿「そ」]い/に[沿「そ」]う/に[沿「そ」]った => Along with A; In line with A N2
Based, Focused, Depending on
ことになっている => Plan, rule, decide N2
Information, Report
ずにはいられない/ないではいられない => Can't help but A; A is unavoidable N2
Will, Decision, “Doing”
にしたら => From A's perspective, N2
Considering, Concerning
もし~たなら => If A … N3
Conditional, While
にいたって => As for A, when it comes to the example A N1
Considering/ Concerning
[全「まった」]く~ない => Not A (at all; even a little bit) N3
Not only, Not even