Your exam is on Wednesday, May 17th.
You must study the past simple: regular verbs ( + / – / ? ) and the 14 irregular verbs we studied.
(More activities at http://www.englisch-hilfen.de/en/exercises_list/zeitformen.htm )
Here are some images from Woodward English that might help you:
Finally, if you’re REALLY good at the past simple already, watch this video about the pronunciation of verbs in the past simple: http://www.grammar.cl/english/pronunciation-ed.htm