Assertion: mound's building | /r/HasProperty | massive undertaking
Facets:
Source sentences:
text: The building of the mound and moat must have been a massive undertaking, since the total effort required the movement of over 60,000 tons of earth.
text: The building of the mound and moat must have been a massive undertaking, since the total effort required the movement of over 60,000 tons of earth.