Passive voice is not understood for certain by Warbler. It is hoped that Warbler has gotten this correct.
Passive voice was used perfectly by Warbler 😊
This pleases Warbler.
A grammatical lesson needs to be taught. However, the lesson may be difficult to teach when one’s sentence structure is limited in this way. For the purposes of instruction, the rules are temporarily suspended. I am allowed to do so, as the rules we created by me!
Passive voice makes the recipient if action the subject of the sentence. If want to make a statement about a ball, a thrower, and the action in the sentence is the throwing off the ball, I have two basic structure: I threw the ball (active); the ball was thrown by me (passive). They say the same thing but the structure is different. In the active voice, I am the subject of the sentence and I’m the one who threw the ball. I’m the passive voice alternative, I’m still the one who threw the ball, I’m still the one performing the action, but now I’m the object of the sentence, while the ball is the subject.
Most of your sentences have been correct, so don’t fret. The quote above is not. This is the subject, and it’s performing the action of pleasing. You are the object. You could have phrased it like this:
Warbler is pleased by this.
The key ingredients to a passive voice sentence are:
A form of ‘to be’: be, is, am, are, was, were, being, been
plus
joining with the past gerund form (the form created when used with a form of have, i.e. have been, has helped) of the action verb.
plus
‘by’ the performer of the action, though often this is implied rather than stated (i.e. ‘by me’)
Again, your sentence should have read: Warbler is [a form of ‘to be’] pleased [past gerund] by this [‘by’ the performer of the action, though this is optional].
The rules will now be enforced.