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Once you login to ZoneCours with your student ID and password (the same one you use for your email), you arrive in what is called Espace personnel. In the vertical menu of the left, click on the option Préférences (second from the bottom).
Once on that page, click on Langue.
Select English- United States and click on the blue button Mettre à jour les options to finalize the change of language.
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Also, if you click on any tool in the vertical menu on the left in a course site (e.g. Announcement, Assignments, etc.), on the top right of the interface for that tool, there is a button Help. This will lead you directly to the online help for that specific tool.