Нужна помощь, как сделать? Passive Voice

Change the following sentences into the passive voice:
1.He didn’t clean the room yesterday.
2.I shall send a letter to my friend next Monday.
3.Who wrote this book
4.We were discussing the text when he entered.
5.They have already chosen the topic of the discussion.
6.When did you receive this information.
7.He must feed his pet every day.
8.My grandfather built this house twp years ago.
9.What pets do people keep in their houses
10.I shall give her all the papers tomorrow.
11.We always help him when he is in trouble.
12.If you don’t take me to the station, I will miss the bus.
13.Will you return the book to Mary tomorrow?
14.We don’t usually write articles about music for the school newspaper.
15.How many friends will you invite to the party?
16.My mother didn’t help me write the essay in English.
17.Do you often help your mother about the house