go along with somebody in his evil deeds 同流合污

同流合污，汉语成语，原指思想、言行同不好的风俗、世道结合。现在多指跟坏人一起做坏事。可以翻译为“go along with somebody in his evil deeds，join somebody in his evil doing”等。

例句：

别跟他们同流合污。

Don't go along with them in their evil deeds.