https://quizlet.com/_3y0yhw
https://www.goconqr.com/es-ES/p/11357317-PRESENT-PERFECT-SIMPLE-mind_maps
https://www.agendaweb.org/verbs/present_perfect-exercises.html https://www.englishpage.com/verbpage/verbs5.htm https://www.ego4u.com/en/cram-up/grammar/simpas-preper/exercises https://www.ego4u.com/en/cram-up/grammar/simpas-preper/exercises?ex02