Assertion: beryllium | /r/HasProperty | easy
Facets:
value: to form a compact protective film
type: PURPOSE
value: because of its surface
type: CAUSE
Source sentences:
text: (1) Beryllium is easy to form a compact protective film because of its surface, but it does not react with water, while other metals magnesium, calcium, strontium and barium react with water easily.