~ともあろうものが      => of all people (expression showing surprise at a high standing person's misbehavior) N1
~ものとおもう => Believe~ N1
Speculation
~であろうとなかろうと => whoever; whatever; however; even ~ N1
Innocent
...というのも => The reason is N2
Cause, reason
だろうと[思「おも」]う => I think probably A N4
Sentence Endings
... というもの => something like; something called ~ N3
Command, definition
... ないもの (だろう) か => isn't there; can't we…?; can't I…? N2
Aspiration
~てからというもの      => ever since ~ N1
というものだ => something like; something called ~ N2
というのも…からだ => This is because… N2
Cause, reason
というものは...だ => something like; something called ~ N3
Explain
というものでもない => there is no guarantee that…; not necessarily ~ N2