Assertion: crossword | /r/CapableOf | become popular
Facets:
value: in the early 1920s
type: TEMPORAL
Source sentences:
text: While crosswords became popular in the early 1920s, it was not until 1942 that The New York Times (which initially regarded crosswords as frivolous, calling them "a primitive form of mental exercise") began running a crossword in its Sunday edition.
text: They became so popular that newspapers began using them, and word enthusiasts began creating them in huge numbers.