Change in to passive voice: Somebody has taken my briefcase. The teacher returned our written work to us

1.somebody has taken my briefcase.
2.The teacher returned our written work to us.
3.The mad dog bit the little boy.
4.The police have arested five suspects.
5.The doctor ordered him to take a long rest.
6.Lightning struck the house.
7.A group of students have met their friend at the railway station.