When should I use perfect or the imperfect tense?

The perfect tense refers to events in the past that are definite and complete. It can often be used when something in the past relates to something happening in the present. It is translated at 'i have' or 'i have been' doing something. E.g. I have paid the bill, j'ai payé l'addition or I have been dancing this evening, ce soir j'ai dansé. The imperfect refers to continuous events in the past or events that were not complete. While the perfect tense refers to a specific action, the imperfect often doesn't have an exact time frame and is used to describe events which give background information. It can also be used for an event that happened repetitively in the past or an event that started in the past and continues to the present. E.g. he did this every day, il faisait cela chaque jourE.g. he has been working since 7am, depuis 7h il travaillait