Turn into passive voice:
1.When I entered the office, the principal told me something which i didn`t understand.
2.They were not going to tolerate it any more.
3.Seeing that ,I kept silent.
4.I nodded my head, which he took as some sign of promise.
5.He started down at it.
6.The morning sun was tempting him to close his eyes.
7.Boys are leaving the school.
8.Students send special invitations to their friends and relatives asking them to come to the ceremony.