Assertion: moon's phase | /r/HasProperty | understood
Facets:
value: well
type: DEGREE
value: easily
type: MANNER
Source sentences:
text: The phases of the moon are easily understood once one examines the relationship between the moon, the Earth, and the Sun.
text: Since the phases of the moon are well understood, along with the orbital patterns of the Earth, solar eclipses are very easy to predict.