Assertion: lung's wall | /r/HasProperty | strengthened by stiff rings of cartilage
Facets:
value: to keep it
type: PURPOSE
Source sentences:
text: The walls of the trachea (pronounced: TRAY-kee-uh) are strengthened by stiff rings of cartilage to keep it open.
text: The walls of the trachea (pronounced: TRAY-kee-uh) are strengthened by stiff rings of cartilage to keep it open.
text: The walls of the trachea (TRAY-kee-uh) are strengthened by stiff rings of cartilage to keep it open.