[Clarence] went bike riding his grandson [Michael]. [Michael]'s father [Nicholas] was skateboarding.
('Nicholas', 'Clarence')
[Clarence] went bike riding his grandson [Michael]. [Michael]'s father [Nicholas] was skateboarding.
[{('Nicholas', 'father', 'Clarence'): [('Nicholas', 'son', 'Michael'), ('Michael', 'grandfather', 'Clarence')]}]
['son', 'grandfather']