Assertion: bursa | /r/CapableOf | protect muscle
Facets:
value: by reducing friction
type: MANNER
Source sentences:
text: The bursa is a fluid-filled sac that helps protect muscle, ligaments, tendons, or skin that rubs across bone.
text: A bursa is a tiny sac filled with fluid that protects the bones, tendons and muscles by reducing friction, notes WebMD.