Question: when moon completely covers sun what's it called
[{'answer': 'solar eclipse', 'provenance': [{'wikipedia_id': '5024887', 'title': 'Solar eclipse', 'start_paragraph_id': 1, 'start_character': 2, 'end_paragraph_id': 1, 'end_character': 15, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]