Question: what is the left lane of a motorway used for
[{'answer': 'passing', 'provenance': [{'wikipedia_id': '1148773', 'title': 'Passing lane', 'start_paragraph_id': 1, 'start_character': 2, 'end_paragraph_id': 1, 'end_character': 9, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1148773', 'title': 'Passing lane', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 324, 'bleu_score': 0.915132941383415, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9455508451572141989}, 'section': 'Section::::Abstract.'}]}]