No one has used this sewing machine for several months
->this sewing machine hasn't used for several months.
the children are drawing pictures about their ideal world
->pictures are being drawn by the children about their ideal world
they awarded him the Nobel prize for medicine in 1946
-> the Nobel prize was awarded to him for medicine in 1946
we saw him leave the office at 6 o'clock this morning
->He was seen leaving the office at 6 o'clock that morning
you ought to water these plants once a week
->these plants ought to be watered once a week by you
people saw her driving a car near the bridge
-> she was seen driving a car near the bridge
the said that he was the richest man in the town
-> he was said to be the richest man in the town
scientists began to carry out researches on AIDS in 1981
->researches on AIDS was begun to carry out in 1981 by scientists
everybody believed that he had died of lung cancer
-> he was believed to have died of lung cancer
people can't learn a foreign language in a short time
-> a foreign language can't be learned in a short time
did anyone ask any question about me
->was any question asked about me?
the robbers forced the bank manager to hand over the money
-> the bank manager was forced to hand over the money by the robbers
they let us go
-> we are allowed to go by them
some people think he is a dangerous criminal
-> he is thought to be a dangerous criminal
no one told me the truth
-> i wasn't told the truth