Assertion: spadefoot's habitat | /r/HasProperty | challenging
Facets:
value: to research
type: TRANSITIVE-OBJECT
value: very
type: DEGREE
Source sentences:
text: This habitat is very challenging to research, and as well as being little-studied, it is vast, with 79% of the Earth's biosphere being at depths greater than 1,000 m (3,300 ft).