Answer:
1. The mouse was eaten by the cat.
2. The walk was done by my dog and I.
3. The fan sign event was attended by me.
Step-by-step explanation:
The passive voice is a way of rendering a sentence such that the action is performed on the subject. It is the opposite of the active voice were the subject performs the action. In each of the sentences above, the action is done by the subject. To change the first sentence to a passive voice, the action which is, 'to eat', was made to act on the subject. Thus, we have, the resulting sentence; "The mouse was eaten by the cat."
The second sentence seems a bit confusing but following the logic of the action acting on the subject, we render the sentence such that the walk is done by the dog and the person in question. The same logic was applied to the last sentence.