Put the sentences into passive voice. Mind the tenses.
Shakespeare might have written more than 40 plays.
More than 40 plays
Bill has read all these books.
All these books
Mary has just copied Tom's homework.
Mr. Delicious is cooking the dinner tonight.
by Mr. Delicious tonight.
Harry and Sally could have left this book here.
by Harry and Sally here.
Martin is going to buy this dog.
After Frank had visited Tom, Sam came along.
by Frank, Sam came along.
Steven has bought these flowers.
Dan copied Jack's homework yesterday.
by Dan yesterday.
James is joining the party soon.
by James soon.