[Keith] asked his father, [Rich], to help him with his math homework. [Rich] could n't, because he was lousy at math himself. [Keith] and his brother [Dale] like to go to the movies every weekend. [Cheryl] has started to accompany her brother [Dale] to the movies whenever he goes.
('Cheryl', 'Rich')
[Keith] and his brother [Dale] like to go to the movies every weekend. [Cheryl] has started to accompany her brother [Dale] to the movies whenever he goes. [Keith] asked his father, [Rich], to help him with his math homework. [Rich] could n't, because he was lousy at math himself.
[{('Cheryl', 'father', 'Rich'): [('Cheryl', 'brother', 'Dale'), ('Dale', 'father', 'Rich')]}, {('Dale', 'father', 'Rich'): [('Dale', 'brother', 'Keith'), ('Keith', 'father', 'Rich')]}]