Grammar Question. What is the difference between the passé composé, the imparfait and the passé simple?

The three tenses are used to describe actions which happen in the past. The passé composé describes a one-off action in the past which is now completed. Eg. Yesterday, I went to the market. // Hier, je suis allé(e) au marché. The imparfait, or the imperfect tense in English, describes an action which was ongoing in the past. This can be either: 1. A routine you used to do. A good way to remember this is to ask yourself, could I include 'used to' when explaining it in English. E.g. I used to wake up every morning at 7. // Je me réveillais tous les matins à 7h. OR 2. An action which you were in the middle of when something interrupted you. Eg. I was walking to school WHEN I fell. // Je marchais à l'école QUAND je suis tombé(e). The passé simple is effectively the same as the passé composé, but used for actions in the very distant past, such as in historical books, obituaries. Eg. He was born in 1928. // Il naquit en 1928.