Assertion: narwhal's tooth | /r/CapableOf | spike an ice flow
Facets:
value: to spear fish
type: TRANSITIVE-OBJECT
value: for napping
type: PURPOSE
Source sentences:
text: Over the years, people have speculated that the tooth serves to dig around in the ocean bottoms uncovering food; to spike an ice flow for napping, to spear fish, to break ice, as a sexual display or for fighting other males.