get something out of your system

to say or do something that you have been wanting to say or do for a long time, and therefore begin to feel less worried or angry about it

去说或者做你一直想要说或者做的东西，如此之后就能减少你对这些事情的担忧或者愤怒

Get something out of your system “让什么东西离开你的身体”这个表达的实际意思是发泄。把藏在心中许久或忍耐很长一段时间的事情说出来，释放一下。

If something awful happens to you at least you can write about it. I'm sure you feel better if you get it out of your system.

如果有什么不好的事情发生了，至少你可以写下来。我相信如果你把它发泄出来，你会感觉更好。