His marriage was going through a bad patch.他的婚姻正经历困难期。

The company I work for went through a rough patch.我工作的公司经历过一段困难时期。

I went through a bad patch a few years ago: I lost my job and then my wife left me.几年前我有过一段很倒霉的日子：先是丢了工作, 随后老婆也离开了我。