1)And in 1907 they produced the first colour film.2)The brothers kept their new invention as a closely-guarded secret.3)Auguste organized private screening to the invited guests only.
Change these sentences in the Passive Voice

1.The firsr colour film was produced in 1907 by they.2.New invention were kept as a closely-guarded secret be the brothers.3.Private screening was organised to the invited guests only by Auguste