story: [Mark] and his brother [Bernard] were playing tag in the park. [Mary] does n't like her brother [Mark]. [Mark] bought a present for his mother [Crystal].
query: ('Mary', 'Bernard')
clean_story: [Mary] does n't like her brother [Mark]. [Mark] and his brother [Bernard] were playing tag in the park.
proof_state: [{('Mary', 'brother', 'Bernard'): [('Mary', 'brother', 'Mark'), ('Mark', 'brother', 'Bernard')]}]