Assertion: cello's endpin | /r/HasProperty | retractable
Facets:
Source sentences:
text: Modern endpins are retractable and adjustable; older ones were removed when not in use.
text: Modern endpins are retractable and adjustable; older ones were removed when they are not used.
text: Modern endpins are retractable and adjustable; older ones were removed when not in use.