Yes! You may re-take any of your courses when it's offered in a future session. Each offering of a course is assessed independently and most edX courses do repeat. Please note that payment for one session doesn't apply to a future session: Can I transfer to another session?
However, it's not possible to start fresh or reset your course progress in the same session.
Note: Un-enrolling from and re-enrolling in the same course session won't reset your course progress.
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