What are the key features of a successful online course? Your response should contain at least 3 placeholders represented by square brackets, such as [course name]. Highlight at least 2 sections in your answer with markdown, i.e. *highlighted section*. Your answer must contain a title, wrapped in double angular brackets, such as <<key features of a successful online course>>. In your response, the word "engagement" should appear at least 2 times.

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