PRESENT PERFECT

1   http://learnenglish.britishcouncil.org/es/english-grammar/verbs/present-tense/present-perfect

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

3  http://www.focus.olsztyn.pl/en-present-perfect-tense-exercises-with-answers.html#.Vuv9z-LxxBc

4 http://www.montsemorales.com/gramatica/PresPerf1.htm

5 http://www.english-grammar-lessons.com/presentperfect/exercise4.swf

6 http://www.adelescorner.org/grammar/pres_perfect/pres_perfect_1.html

7 http://suz.digitaleschulebayern.de/english/grammar/presperfs4.htm

8 http://mrbrownslearningspace.com/wp-content/uploads/2015/01/Present_Perfect_3.htm

9 http://www.montsemorales.com/gramatica/PresPerf1-B.htm

10 http://www.montsemorales.com/gramatica/PresPerf2pdc.htm

11  http://www.learnenglish.de/games/tenses/prespersim.html

VIDEO

1  https://www.youtube.com/watch?v=XNpdB5_3GhE

2 https://www.youtube.com/watch?v=Dkln8PfE1xE&ebc=ANyPxKojr5eDE_dVD0fwQVJL8xX5sY-ZlhRYUB6wCxP0o0s0kNAnNq4GZUOS_HZeYHMX7CHIZBKJp7NiWHW3_S1lFnm-Cbv2Qw