1.Nobody has answered my question properly
My question hasn't been answered properly.
2.They didn't tell me the truth about the situation.
The truth wasn't told to me about the situation.
3.No one can answer the question
The question can't be answered.
4.They built two new houses last year.
Two new houses were built last year.
5.People were carrying the chairs out into the garden
The chairs were being carried out into the garden.
6.People will laugh at you if you wear that silly hat.
You will be laughed at if you wear this silly hat.
7.You mustn’t throw away empty bottles.
Empty bottles mustn’t be thrown away.
8.They left the wounded behind.
The wounded was left behind
9.I have sharpened the knives
The knives have been sharpened.
10. There’s a new block of flats they are building down the road.
A new block of flats is being built down the road.