Assertion: futon | /r/CapableOf | become popular
Facets:
value: in the 1980s
type: TEMPORAL
value: in the u.s.
type: LOCATION
Source sentences:
text: Futons became popular in the U.S. in the 1980s, after William Brouwer, who was inspired by the traditional Japanese versions, invented the futon sofa bed in 1982.