Because the melody changes and not all harmonies are concordant with every note.

由于旋律在不停变化而且不是所有的和弦都和每个音符一致。

耶鲁公开课 - 聆听音乐课程节选

It just depends on the areas of town, I think. They're always changing, you know.

我认为这取决于城市中不同的区域。他们总是在不停地变化。

上西区的富人 - SpeakingMax英语口语达人

The constraint isn't constant temperature because the temperature is going to be changing.

是在不停变化的，不是恒压,因为我们已经有Δp了。

麻省理工公开课 - 热力学与动力学课程节选