Assertion: penguin's nest | /r/MadeOf | grass
Facets:
value: each year
type: TEMPORAL
Source sentences:
text: The birds nest under forest canopy, in caves, under boulders and shrubbery, and in nests made of brush and grass.
text: Breeding pairs, most of which are monogamous, construct new nests made of stones, grasses, and debris each year.