Assertion: bird's forelimb | /r/HasProperty | wing
Facets:
Source sentences:
text: Birds have various adaptations for flight, including a lightweight skeleton, two large flight muscles, the pectoralis (which accounts for 15% of the total mass of the bird) and the supracoracoideus, as well as a modified forelimb (wing) that serves as an aerofoil.
text: Birds have forelimbs that are covered with feathers and are called wings.