Similarly, just as we have symbols for the presence of sound and its length, we have symbols that represent the absence of sound.

类似的,既然我们有符号,来表示声音的频率和长度,我们也有表示静音的符号

耶鲁公开课 - 聆听音乐课程节选

Wireless communication devices must be silenced.

无线通讯的设备必须是静音的。

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