Assertion: barnacle's plate | /r/HasProperty | pushed outward
Facets:
value: at full tide
type: TEMPORAL
value: to allow
type: PURPOSE
Source sentences:
text: With muscular contractions these plates can be opened or closed, depending on the state of the tide: at full tide, the plates are pushed outwards to allow the barnacle to feed, but as the tide withdraws, the barnacle closes its shell once again, leaving just a tiny opening for oxygen to enter.