Question: when did the us get involved in world war 1
[{'answer': 'April 1917'}, {'provenance': [{'wikipedia_id': '25604889', 'title': 'United States in World War I', 'start_paragraph_id': 5, 'start_character': 0, 'end_paragraph_id': 5, 'end_character': 794, 'bleu_score': 0.789703750532153, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13703647866909511404}, 'section': 'Section::::Entry.\n'}]}]