SIMPLE PAST

http://www.isabelperez.com/happy/tenses/exercises/past_quest1.htm

http://www.isabelperez.com/happy/tenses/exercises/past_mistakes.htm

http://www.ego4u.com/en/cram-up/grammar/simple-past/exercises
http://www.inglesonline.com.br/exerciciosdeinglesonline/past-verbs-affirm.htm

http://www.ego4u.com/en/cram-up/grammar/exercises?tense=1&level=0&type=positive

http://www.ego4u.com/en/cram-up/grammar/exercises?tense=1&level=0&type=question

http://web2.uvcs.uvic.ca/elc/StudyZone/330/grammar/irpast1.htm

http://www.englisch-hilfen.de/en/exercises/questions/simple_past2.htm