Assertion: crustacean | /r/HasAspect | hard shell
Facets:
Source sentences:
text: Crustaceans have a hard shell to protect themselves from their enemy.
text: Quick facts Crustaceans are aquatic animals that have jointed legs, a hard shell, and no backbone.
text: Crustaceans are aquatic animals that have jointed legs, a hard shell and no backbone, such as crab, crayfish, lobster, prawns and shrimp.