1. Our students are discussing an interesting subject. - An interesting subject is being discussed by our students.
2. They will finish their work in time. - Their work will be finished in time.
3. She has just written the task. - The task has just been written by her.
4. She was writing a letter when I came in. - A letter was being written by her when I came in.
5. He wrote a new detective story. - A new detective story was written by him.
6. I have broken my favourite cup. - My favourite cup has been broken by me.