http://www.englisch-hilfen.de/en/exercises_list/passiv.htm
http://www.eslgamesplus.com/verb-tenses-interactive-grammar-game-for-esl-jeopardy-quiz-game/
https://www.ego4u.com/en/cram-up/grammar/passive/exercises?present-perfect
http://www.verbs-online.com/english-verbs/english-verbs.htm
http://www.englisch-hilfen.de/en/exercises/tenses/present_perfect_statements.htm
http://www.really-learn-english.com/present-perfect-exercises.html