Assertion: vein's artery | /r/CapableOf | form circle
Facets:
Source sentences:
text: These arteries form a circle known as Willis' circle, which is named after Thomas Willis, the British physician who discovered it.
text: Because the carotid and vertebrobasilar arteries form a circle, if one of the main arteries is occluded, the distal smaller arteries that it supplies can receive blood from the other arteries (collateral circulation).