Sätze ins Passiv setzen

Hallo zusammen,

sitze schon länger an einer Aufgabe, inder man die Englischen Sätze ins Passive setzen muss.
Ich versteh das irgendwie nicht ganz so :( Kann mir jemand helfen, ob ich die Sätze richtig gemacht habe und wäre so lieb und mir sie richtig zeigt? Danke schonmal. Hier sind die Sätze:

1. They are offering guided tour around the city at reduced prices today.

--> Today are offered guided tours around the city at reduced prices.

2. You must not leave baggage unattended.

--> Baggage must not left unattended.

3. Someone has stolen Katrin`s handbag.

--> Katrin`s handbag are stolen by someone.

4. They built thi church in 1648.

--> This church are built in 1648.

5. You can buy tickets for the trip when you get on the bus.

--> When you got on the bus ou could bought tickets for the trip.

6. We should do more to save our old buildings.

--> To saved our buildings we should done more.

7. Angela will send the programms when the printers have printed them.

--> The programms would send by Angela when the printers had printed them.

8. They were preparing dinner when I arrived.

--> When I was arrived they were prepared dinner.

9. Visitors should not park their cars in the spaces for disables people.

--> The cars should not parked by visitors in the spaces for disabled people.

10. Katrin said that Michael had found her handbag behind a chair in the living room.

--> The handbag was found by Michael behind a chair in the living-room, said Katrin.

Wäre lieb, wenn mir jemand helfen könnte und danke schonmal im Vorraus :-)