Assertion: caribou's ground | /r/HasProperty | soft
Facets:
Source sentences:
text: Reindeer hooves expand in summer when the ground is soft and shrink in winter when the ground is hard.
text: In the summer when the ground is soft, the hooves expand and become sponge-like to help provide traction.
text: In summer, when the ground is soft and wet, their footpads expand again, giving the reindeer better traction.