1. Q044
Whom are you accusing of treachery? It was he— not me—who swore unwavering love and loyalty to you.
Change ...
Whom > Who
he > him
me > I
No change needed
You need whom if the verb already has a subject. Notice that the verb are accusing does have you as its subject, so the whom is correct.
After a linking verb like was, use the subjective form of the pronoun. He is that correct form.
Nice move! Because was is a linking verb, you need a subject pronoun to follow. I is the subjective form.
Whoops! There is a problem.