Answer:
1. Portuguese is spoken in Brazil
2. This house was built by my grandfather in 1943.
3. Guermnica was being painted by Picasso at that time
4. The office has been cleaned by the cleaner.
5. Three books had been written by him before 1867.
6. You will be briefed by John later
Step-by-step explanation:
The sentence's have been changed from active to passive voice.
P. S: The writing was so messed up, but I did my best to clean it up and answer.