Assertion: viper's fang | /r/CapableOf | rotate out at precise time
Facets:
value: to not damage the fangs
type: PURPOSE
Source sentences:
text: The fangs can rotate as a pair or individually, during a strike the mouth of the viper can open to nearly 180 degrees, the fangs then rotate out at a precise time, to not damage the fangs, and the snake bites down clamping its jaws tightly excreting the poison from the glands.