English exercices 8°

http://www.ego4u.com/en/cram-up/grammar/present-perfect-simple/exercises?03

http://www.nspeak.com/newbasic/grammatica/presperfect.htm

http://www.english-grammar-lessons.com/presentperfect/exercise2.swf

http://www.ego4u.com/en/cram-up/grammar/present-perfect-simple/exercises

http://www.englishbee.net/lessons/inter_exer/present_perfect/close_2/close_2.htm

http://www.english-grammar-lessons.com/irregularverbs/exercise6.swf

https://www.youtube.com/watch?v=y04Ph6D0kTw

http://www.eslgamesplus.com/present-perfect-vs-past-tenses-rally/