Assertion: duck's layer | /r/HasProperty | outer
Facets:
Source sentences:
text: Preening is the process by which ducks groom themselves—getting rid of dust, dirt, and parasites from their feathers, while also helping to waterproof their outer layer.
text: Preening is the process by which ducks groom themselves—getting rid of dust, dirt, and parasites from their feathers, while also helping to waterproof their outer layer.