Assertion: penguin's layer | /r/CapableOf | trap air
Facets:
value: beneath it
type: LOCATION
Source sentences:
text: This is because penguins need their feathers to overlap in order to form a thick yet smooth layer which traps air underneath it.
text: The feathers of a penguin are relatively short and stiff in comparison to those of other birds, and they overlap closely to form a thick, smooth layer which traps air beneath it and so provides insulation from the cold.