Passive Voice

USE - Passive Voice is used to place emphasis to the action, not to the DOER.

Why do you think Royboy omitted the subject in the last panel?
YES, because he wanted to omit the DOER - HIMSELF.

Not to say: "I made mistakes, mom."

STEPS TO FORM PASSIVE VOICE:

1. The object becomes the subject. So, in the sentence above:

MISTAKES

2. Verb BE in the same 'tense' of the active voice, and in this example it is THE SIMPLE PAST:

Mistakes WAS

3. Past Participle (3rf column) of the MAIN VERB:

Mistakes were MADE.

4. If Royboy wanted to tell his mother what he made, he could ADD:

Mistakes were made BY ME.

IT WILL ALWAYS DEPEND ON THE INTENTION, THE PURPOSE.