1. The book was written by a famous writer. A famous writer wrote the book.
2. I was offered a good job by them. They offered me a good job.
3. My dog has been stolen by somebody. Somebody has stolen my dog.
4. This article will be written tomorrow by Natasha. Natasha will write this article tomorrow.
5. The doctor was sent for by my mother. My mother sent for a doctor.
6. I am often punished by my parents. My parents often punish me.