Assertion: sea urchin's test | /r/HasProperty | hard shells
Facets:
Source sentences:
text: Their tests (hard shells) are round and spiny, typically from 3 to 10 cm (1 to 4 in) across.
text: The sea urchin has a globe-shaped body, sharp spines, and a hard test, or shell.
text: Their tests (hard shells) are round and spiny, typically from 3 to 10 cm (1 to 4 in) across.