を中心に => focused on; centered on~ N2
[中心「ちゅうしん」]に => With A as the center N2
Miscellaneous
ままになる => Just let... N4
Continuous
~きわまる/きわまりない(~極まる/極まりない)      => extremely; very ~ N1
までになる => becoming ~ N2
Reach level
まるで...ない => Absolutely not... N3
Emphasize the negative meaning
~ないではすまない / ずにはすまない      => must; will definitely; can't help but to ~ N1
まもなく => soon; shortly; before long N3
Short period of time
...まもなく => soon; shortly; before long N3
Short period of time
たまらない => can not bear N2
Emphasis on degree
いまさらながら => Still ... now N3
Time
まだV-られない => Not yet ~ N4
Ability