Assertion: gull's back | /r/HasProperty | dark gray
Facets:
value: to sooty black color
type: TRANSITIVE-OBJECT
value: during the summer months
type: TEMPORAL
Source sentences:
text: Their back and wings are a very dark gray to sooty black color.
text: Their back and wings are a very dark gray to sooty black color.
text: During the summer months, the adult's back and wings are dark gray, and the trailing edge of their wings is white, with a black wing-tip.