てもらえないか => could you please ~ N3
Request
てやってもらえないか => Could you...help me, please? N3
Suggestion
なければならない/なくてはならない/なければいけない/なくてはいけない/なければだめ/なくてはだめ => must N5
あえて~ない => Not trying to find a way N2
Emphasize
てならない => Very A; Extremely A N2
Degree, Level, Amount
てならない => can't help but; dying to; extremely ~ N2
てはならない => must not; cannot; should not ~ N2
くらいなら/ぐらいなら => rather than (do …)​ N1
と思っている => Plan to do something N4
Plan
~といえなくもない => It can be said that ~ N1
Concession
ようと思う/ようと思っている => thinking of doing; planning to ~ N3
... おぼえはない => don't remember... N3
Position, perspective