In this English vocabulary lesson, you will learn 5 expressions to describe the frequency of an action. The frequency of an action describes ... ... <看更多>
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In this English vocabulary lesson, you will learn 5 expressions to describe the frequency of an action. The frequency of an action describes ... ... <看更多>
Frequency is the number of repeats of this cycle per second. It's the same for the particle movement and the pressure increase/decrease ... ... <看更多>