Assertion: locksmith's knowledge | /r/HasProperty | essential
Facets:
value: for those locksmiths
type: TRANSITIVE-OBJECT
Source sentences:
text: A strong working knowledge of electricity and electronics is essential for those locksmiths who will be installing security systems, safes, and the like.
text: A working knowledge of lock types, key types, and key-cutting machines is essential, of course.