Here are some links to practice the past simple affirmative.
90% to past to the next exercise.
http://www.bradleys-english-school.com/online/matchingpairs/mpiregpast1.html
http://www.montsemorales.com/gramatica/IrregularPDC23-1b.htm
http://www.agendaweb.org/exercises/verbs/past-simple-regular
http://www.agendaweb.org/verbs/past-simple-regular/index.html
http://www.agendaweb.org/exercises/verbs/past-simple-regular-d-ed-ied.htm
Negative.
Remember you need a 90% to pass
http://www.montsemorales.com/gramatica/PastSimplNeg2-Sw2-5.htm
http://www.english-room.com/negative_6.htm
http://esl.fis.edu/grammar/single/pastsimp2.htm
http://www.englishlab.net/hp/quiz11_past_simple_3_negative_sentences.htm
