Ответ:

  1. A new dictionary has been bought.
  2. A new TV centre has been opened by the government.
  3. The letters have been posted.
  4. This news has been broadcast.
  5. Our cottage has been painted green.
  6. The new project has been finished by her.
  7. A new theatre has been opened in the city.
  8. All the details of our future journey have been discussed.
  9. The poem has been learnt by heart by Alice.
  10. Dinner has been served by Brenda.