English Translation
One of the piano strings is broken.
I suggest “gebrocken” is a exponentially better than “gerissen” which has a multitude of varying meanings in informal language.
“to break” and “brechen” are not the same.
English “to break / broken” is more often used in the general sense of “defective”, and a good german translation might be “kaputt (gehen)”.
German’s “brechen” family is reserved for “breaking by over-bending”, and “reißen/gerissen” is used for “breaking by tearing / excessive pulling forces”.
So in the case of piano strings, the only sensible translation is “gerissen”, or if the mode of failure is really unknown, then “kaputt”. Although “kaputt” is rather colloquial, and “defekt” would be a formal alternative.
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