"Frequency" just means the rate at which air molecules go back and forth, or a voltage fluctuates, and it can be represented as the rate at which a regular squiggle goes up and down.

频率“通常是指空气粒子来回运动的速率或者电压的波动，所以它能代表一个规则波形曲线上下波动的节律。”

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Each time she moved up in vibration, the weekend with her son would cause her to roll back in frequency and become ill.

每次她提高振动，但到周末和她儿子呆一起时就导致她频率回跌而生病。

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An Earth station beams a signal up to the satellite at a certain frequency, and the craft bounces it back down to another, predefined Earth station.

地面基站先用特定频率向卫星发送数据，然后卫星再将把这些数据转发给其它预先确定的地面基站。

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In the case of owned-and-operated stations, the networks could then sell the frequency freed up back to the FCC, which is hungry for more bandwidth to support wireless communications.

FORBES: Why The Networks' Threat to Stop Broadcasting Is Worth Taking Seriously