Handout has 73 fill in the blanks with the Imperfect or Preterit as students listen to the audio. The link for the audio is on the handout.
Since it's a longer listening activity, I usually pair the students. Also I do one page at a time. Each time we review before continuing onto the next page. As we review the fill in the blanks, students discuss why the Preterit or the Imperfect was used. This normally takes about 45 mins. If you only have 30 mins. class period, the activity can be done over two days or do part of it in class and assign the rest for HW.