を[機「き」]に => Use A as an opportunity N1
Time, Situation
を[契機「けいき」] => As a good opportunity A, (do) B N2
Information, Report
ようになる/なくなる => Become… N3
Time, Situation
なり~なり => A or B N1
Lists, examples
ないものでもない/ないでもない => A is not completely impossible N1
Need/Requirements
ねばならない => Must A N2
Needs, Requirements
なければならない => Must do A; have to A N4
Can, Should, Must
にほかならない => Only A N2
Reason, Result, Response
てならない => Very A; Extremely A N2
Degree, Level, Amount
なら => If N4
Conditional
てかなわない => A is a problem N2
Adjectival, Descriptions
なかなか => It is hard to do A, N2
Adjectival, Descriptions