1) They called in the police to deal with the situation.
The police were called to deal with the situation.
2) He gave me very helpful advice.
The advice he gave me was very helpful.
3) She didn't make very impressive progress.
The progress she made wasn't very impressive.
4) They are developing the city centre.
The city centre is being developed by them.
5) They lost their luggage during the flight.
Their luggage was lost during the flight.