GRAMMAR:

http://www.englisch-hilfen.de/en/grammar/passive.htm

Passives with 2 objects:

https://www.englisch-hilfen.de/en/grammar/passive_two_objects.htm

http://myenglishgrammar.com/lesson-15-active-and-passive-voice/3-passive-sentence-with-two-objects.html

Constructions with like it is believed / it is thought...)

https://www.grammarbank.com/it-is-said-that.html

CAUSATIVE PASSIVE / HAVE/ GET SOMETHING DONE

ACTIVITIES:

Passive with two objects:

http://www.ego4u.com/en/cram-up/grammar/passive/exercises?07

http://www.englisch-hilfen.de/en/exercises/active_passive/objects_tenses.htm

http://www.tolearnenglish.com/exercises/exercise-english-2/exercise-english-4216.php

http://wwwedu.ge.ch/cptic/prospective/projets/anglais/exercises/passive2.htm

http://wwwedu.ge.ch/cptic/prospective/projets/anglais/exercises/passive3.htm

http://wwwedu.ge.ch/cptic/prospective/projets/anglais/exercises/passive4.htm

http://mbonillo.xavierre.com/exercises/bch2/2bch2007/passive1.htm

http://mbonillo.xavierre.com/exercises/bch2/2bch2009/passrph2bch6.htm

http://www.englishexercises.org/makeagame/viewgame.asp?id=6854

Impersonal passive:

https://www.ego4u.com/en/cram-up/grammar/passive/exercises?09

http://passivecausality.weebly.com/personal-and-impersonal-constructions.html

https://www.ejerciciosinglesonline.com/impersonalpassive/

https://www.englishexercises.org/makeagame/viewgame.asp?id=6854 

HAVE SOMETHING DONE (Causative have):

http://www.ego4u.com/en/cram-up/grammar/participles/exercises?08

https://www.perfect-english-grammar.com/causatives-exercise-1.html

https://www.perfect-english-grammar.com/causatives-exercise-2.html

https://www.esl-lounge.com/student/grammar/4g1-causative.php

http://www.focus.olsztyn.pl/en-causative-have-exercises-online.html#.Xrut6sBS_IU

https://www.tolearnenglish.com/exercises/exercise-english-2/exercise-english-119087.php

http://www.englishgrammarsecrets.com/havesomethingdone/menu.php

http://www.autoenglish.org/modalverbs/havedone.htm

http://www.autoenglish.org/modalverbs/gr.havedone.pdf