What is the passive form of these sentences ?

1. They gave up the search after three hours. 
2. They ought to have pointed that out to me at the very beginning. 
3. No one brought up that question at the meeting. 
4. Someone should look into the matter. 
5. It was clear that the parents had brought the child up well. 
6. We had to put off our visit until later. 
7. I was shocked to hear that someone had broken into your house. 
8. They gave me to understand that they would call on new services if they needed them. 
9. Don’t speak until someone speaks to you. 
10. He will stop showing off if people take no notice of him. 
11. His bank manager turned down his request for a loan.  
12. They are putting up many new buildings in London. 
13. You must account for every penny you spent. 
14. They pointed out that no one could deal with the matter until they knew all the facts. 
15. Someone hasn’t stuck this stamp on very firmly.
16. Police had to break the meeting up. 
17. Events will bear out the truth of what I’m saying. 
18. An official held us up at the Customs for half an hour. 
19. How can we bring about the desired result? 
20. He hates people making fun of him.