- action taking place before a certain moment in time
- puts emphasis on the course or duration of the action
Result
- action taking place before a certain moment in time
- puts emphasis on the result
period of time
- action that started before a certain moment and lasts beyond that moment
- actions taking place at the same time
moment in time
- action that takes place once, never or several times
- actions that happen one after another
- actions that suddenly take place
