Answer:
1. Chaltu's name was changed by Bona
2. The novel was read by mom in one day.
3. The classroom was painted by Bikila
Explanation:
When writing a sentence in active form, the subject of the sentence acts on the verb while in the passive form, the subject receives the action.
Using the first example for instance, the subject is "Bona" and in active voice, it is written thus: "Bona changed Chaltu's name" with the subject "Bona" acting on the subject "Chaltu's name".
Meanwhile, in the passive form, the subject "Bona" is the receiver of the action, thus: "Chaltu's name was changed by Bona"
