Question: when is opening ceremony of the world cup
[{'answer': 'Thursday , 14 June 2018', 'provenance': [{'wikipedia_id': '57675697', 'title': '2018 FIFA World Cup opening ceremony', 'start_paragraph_id': 1, 'start_character': 55, 'end_paragraph_id': 1, 'end_character': 78, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '57675697', 'title': '2018 FIFA World Cup opening ceremony', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 217, 'bleu_score': 0.6733875638869621, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8177868959827917108}, 'section': 'Section::::Abstract.'}]}]