Assertion: heron's head | /r/HasProperty | seen prey
Facets:
Source sentences:
text: Having seen prey, the head is moved from side to side, so that the heron can calculate the position of the prey in the water and compensate for refraction, and then the bill is used to spear the prey.
text: Having seen prey, the head is moved from side to side, so that the heron can calculate the position of the prey in the water and compensate for refraction, and then the bill is used to spear the prey.