Assertion: kelp's holdfast | /r/CapableOf | keep the algae
Facets:
value: to submerged rocks
type: TRANSITIVE-OBJECT
Source sentences:
text: Some species of this type of algae have structures named ”holdfasts” which keep the algae to submerged rocks.
text: The button-like holdfast keeps the algae from drifting away from its rocky substrate.