Continuous actions or actions in progress
Whenever an action is in progress or is not completed, you will use imperfective verbs. For example:
Present:
Маша разговаривает по телефону (Masha is talking on the phone)
Она готовит ужин (She is cooking dinner)
Past:
Мы смотрели фильм (We were watching a movie)
Сегодня утром я играл в игры (I was playing games this morning)