Now practise PASSIVE VOICE. Unit 4 of our course book.
http://www.ego4u.com/en/cram-up/grammar/passive/exercises?simple-present
http://www.ego4u.com/en/cram-up/grammar/passive/exercises
http://www.ego4u.com/en/cram-up/grammar/passive/exercises?02
http://www.ego4u.com/en/cram-up/grammar/passive/exercises?simple-past
http://www.englisch-hilfen.de/en/exercises/active_passive/sentences_simple_present.htm
http://www.englisch-hilfen.de/en/exercises/active_passive/sentences_simple_past.htm
http://www.english-4u.de/passive_ex2.htm