Assertion: fan | /r/HasProperty | common
Facets:
value: during this intense period of innovation
type: TEMPORAL
Source sentences:
text: During this intense period of innovation, fans powered by alcohol, oil, or kerosene were common around the turn of the 20th century.
text: Then, find a fan with the equivalent mounting (most fans in computers are common sizes-- example, 70 mm, 80 mm, 120 mm, etc.