1. Teacher is going to tell a story.

a story is going to be told by the teacher

2. Mary is cutting a cake with a sharp knife.

a cake is being cut with a sharp knife by mary

3. The children looked at the woman with a red hat.

the woman with a red hat was looked at by the children

4. They have provided the victims with food and clothing.

the victims have been provided with food and clothing

5. You mustn't use this machine after 5:30 p.m.

this machine mustn't be used after 5:30 p.m

6. After class, one of the students always erases the chalk board.

after class, the chalk board is always erased