The preterit and imperfect tenses can be very confusing as you begin to learn them. Often times they are translated to the same words in English and meaning is differentiated and understood through context. It would be a great idea to review both tenses separately before trying to use them together. Go here for preterit review and here for imperfect review. Once you are confident in your conjugations and spelling, give some of the exercises below a shot.
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