[Roy]'s wife, [Mary], could not figure why [Roy] was coming home so late. It turned out [Roy]'s grandson, [David], had asked [Roy] to teach him how to drive.
('Mary', 'David')
[Roy]'s wife, [Mary], could not figure why [Roy] was coming home so late. It turned out [Roy]'s grandson, [David], had asked [Roy] to teach him how to drive.
[{('Mary', 'grandson', 'David'): [('Mary', 'husband', 'Roy'), ('Roy', 'grandson', 'David')]}]