Assertion: frog's eyelid | /r/CapableOf | help keep eye
Facets:
Source sentences:
text: This third eyelid, also called a nictitating membrane, protects the frog's eyes when it is swimming underwater and helps keep the eyes moist when the frog is on land.
text: Frogs have a third eyelid which helps protect their eyes underwater and keeps them moist on land and some frogs even have a patch on top of their heads which is like a third eye.