Here are the volume controls, volume up, volume down and mute.

这里是音量控制，音量增大，音量减小和静音。

One big feature I wish they had was a volume control.

我希望他们拥有的一大功能是音量控制。

The kidneys control plasma volume by controlling how much water a person excretes.

肾脏通过控制一个人排出多少水来控制血浆量。

On an organ, like an organ in a church, the " stops" are things that help control the volume of the organ, and pulling them out makes the organ louder.

在管风琴上， 就像教堂里的管风琴一样，“塞子” 是帮助控制管风琴音量的东西， 将它们拉出会使管风琴声音更大。