Assertion: electric toothbrush's bristle | /r/CapableOf | become worn
Facets:
value: over time
type: TEMPORAL
Source sentences:
text: The head on mechanical toothbrushes should be replaced every three months or so, before the bristles become worn and frayed.
text: Over time, bristles can become worn out, frayed, and too soft, which results in a less thorough cleaning.