Помогите сделать задание по английскому))

Make the sentences passive.
1)The speaker told the audience about the latest news.
2)Russia was the first country to launch the manned space ship.
3)C. Columbus discovered America 200 years ago.
4)We had done the work by the time they came home.
5)She wrote a letter to her sister in England and read it to us.
6)The farmers had picked up the crops before autumn came.
7)A man followed us from the railway station.
8)The workers built a new  factory in the suburds of the city.
9)We didn`t notine the car because it was dark.
10)Our granny had cooked the cake by the time the guests came.