Instruct: Classify a given review as either positive or negative.
Query: a really fun workout DVD

If you went to this class in real life, you'd go back. The "students" are cheerful, healthy girls of different physical types, the instructor is energetic and knowledgable, and the moves are fun. The workouts are only 20 minutes long, so it's great if you're trying to squeeze exercise in before your workday, but you get the benefits (energy for the day, slightly sore muscles the next day) as long as you put plenty of effort into it.