いたします => to do (polite form of します) N4
~いはしまいか => whether or not; considering options N1
Base, base
ました => Did something... N5
Conjugate verbs
... します => Make... become N4
Purpose, target
と言っていました => Someone said... N4
Speaking
てしまっていた => Did by accident / finished N4
Completed
ましょう => let's ~; shall we ~ N5
...にします => to decide on N4
Determined, determined
てしまった => to finish N4
Description
~ました/~ませんでした => Polite, past form of verb N5
Verb suffixes
にもまして => more than…; above ~ N1
ませんでした => Did not... N5
Negation in the past