Assertion: penguin's voice | /r/HasProperty | unique
Facets:
Source sentences:
text: Each penguin has a unique voice, and that’s why they can recognize each other.
text: Penguins have a unique voice or call that they use to find their mates and chicks in large groups of sometimes a thousand penguins or more!
text: The voice of a penguin is unique and can be recognized by others.