changing

v.改变;变化;使不同;(使)变换，改换，变成

change的现在分词

例句：

The orientation of the planet's orbit is changing continuously.

该行星轨道的方向不断变化。

I'm changing my email address but for the meantime you can use the old one.

我要更换电邮地址，不过那个旧的暂时也还可以用。