https://www.ego4u.com/en/cram-up/grammar/present-perfect-simple
http://www.englishpage.com/verbpage/verbs5.htm
http://www.englisch-hilfen.de/en/exercises/tenses/simple_past_present_perfect.htm
http://www.perfect-english-grammar.com/present-perfect-exercises.html
http://www.eslgamesplus.com/present-perfect-vs-past-tenses-rally/
W past simple vs present perfect P
W past simple vs present perfect
http://eslgamesworld.com/members/games/grammar/perfectpast/spin%20wheel%20present%20past%20tenses.ht