question: Which river in the United States is nicknamed Old Man River and is also the chief river of the second largest drainage system on the North American continent?
answerText: Mississippi River
questionEntity.name: Q49
questionEntity.entityType: entity
questionEntity.label: North America
questionEntity.mention: North American
questionEntity.name: Q30
questionEntity.entityType: entity
questionEntity.label: United States of America
questionEntity.mention: United States
questionEntity.name: Q4022
questionEntity.entityType: entity
questionEntity.label: river
questionEntity.mention: river
questionEntity.name: 2
questionEntity.entityType: ordinal
questionEntity.mention: second
answerEntity.name: Q1497
answerEntity.label: Mississippi River