Question

When it is struck, a tuning fork produces an almost pure tone, retaining its pitch over a long period of time.

Accepted Answer

音叉被敲击时，产生几乎纯质的音调，其音量经久不衰

Front	When it is struck, a tuning fork produces an almost pure tone, retaining its pitch over a long period of time.
Back	音叉被敲击时，产生几乎纯质的音调，其音量经久不衰

Struck Tuning Fork Produces Pure Tone Retaining Pitch