What is the difference between using depuis/pendant/pour in French when saying for?

Firstly, we use 'depuis' to describe an action that began in the past and continues into the present. It is formed with 'depuis' and the verb in the present tense. For example; "J'écoute de la mausique depuis deux heures."'Pendant" is used to describe an action in either the past or the future, but it has no relation to the present. For example, "J'ai joué el netball pendant six ans." (An action in the past), or "Tu habitais en France pendant dix mois"Finally, 'Pour', is used to describe to describe an event that only happens in the future. For example, "Elle parlera pour une heure."