1971 U.S. Pro Tennis Championships – singles
{'<entity_0>': '1971 U.S. Pro Tennis Championships – singles', '<entity_1>': '1971', '<entity_2>': 'tennis'}
[['1971 U.S. Pro Tennis Championships – singles', 'sport', 'tennis'], ['1971 U.S. Pro Tennis Championships – singles', 'point in time', '1971']]
The <entity_0> was a men's <entity_2> tournament played on outdoor hard courts at the Longwood Cricket Club in Boston, USA and was part of the <entity_1> World Championship Tennis circuit.
['tennis event']