を中心に => focused on; centered on~ N2
[中心「ちゅうしん」]に => With A as the center N2
Miscellaneous
ひとつには…ためである => Partly because of ... N3
Cause, reason
~ためしに…てみる => to attempt, to test, to try out N1
Invite and advise
始める => to start; to begin to ~ N4
~んがため(に)/~んがための      => in order to ~ N1
ため(に) => For, because… N4
Cause and Effect
~はめになる(~羽目になる)     => to get stuck with (some job); to end up with (something unpleasant) N1
あらためる => to revise; to replace N3
Happens next
をはじめ/をはじめとする => For example, A N2
Lists, Examples
~にしてはじめて      => since at ~ N1
めったに~ない => hardly; rarely; seldom N3