Assertion: gastropod's foot | /r/ObjectUse | used for swimming
Facets:
Source sentences:
text: Their foot is fin-shaped and used for swimming and their shells are very small, thin and fragile, and in some species it has been lost entirely.
text: Bivalves have a muscular "foot" at their front end that is used for movement such as burrowing, or in some bivalves like the razor clams, for swimming.