Please chance these sentences into passive voice.
I am doing sums.
People must not leave valuables here.
He visits the doctor off and on.
I saw him leaving the house.
Somebody has stolen two of my best paintings.
The noise of the traffic kept me awake.
Someone hit him on the head with a stone.
He is writing the book
The police fined him for rash driving.
Why do you tell a lie?
She will invite me.
This surprises me
They were interviewing her for the job