Assertion: vulture | /r/CapableOf | sweep their wings
Facets:
value: backward
type: MANNER
Source sentences:
text: Vultures navigate the shifting air mass by fanning and folding their flight feathers, sweeping their wings backward, manipulating slotted tips in their primary feathers and rocking sideways on highly cambered wings that in turkey vultures are tilted in a slight dihedral or "V" shape.