Assertion: whistle | /r/HasProperty | blown by referee
Facets:
value: during a sporting event
type: TEMPORAL
Source sentences:
text: The modern era of whistle use began in 1878 when a whistle was first blown by a referee during a sporting event.
text: whistle-blower” are murky — one theory holds that it’s a reference to the whistle blown by British policemen when they saw foul play, and another says it’s a sports reference to the whistles blown by referees