[{"text": "What are the free online courses?", "sentence_id": 1}, {"text": "why are they mixed?", "sentence_id": 1}, {"text": "What are free open online courses?", "sentence_id": 1}, {"text": "What sort of results?", "sentence_id": 1}, {"text": "are those common?", "sentence_id": 2}, {"text": "Why is the percentage for completion so low for MOOCs?", "sentence_id": 2}, {"text": "Why do they drop off?", "sentence_id": 3}, {"text": "what did the other half do?", "sentence_id": 4}, {"text": "What percentage?", "sentence_id": 5}]