Assertion: piano's key | /r/HasProperty | struck
Facets:
Source sentences:
text: When the key is struck, a chain reaction occurs to produce the sound.
text: When the key is struck, the motion on the wippen throws the spoon forward, pushing the lower end of damper lever forward, and releasing the damper from its contact with the string.
text: When the key is struck, a chain reaction occurs to produce the sound.