“卧薪尝胆”，汉语成语，字面意思是“sleep on the brushwood [sticks] and taste the gall”，形容一个人忍辱负重，发愤图强（put up with an insult in order to take revenge，endure hardships to accomplish some ambition）。

例句：

微软已经坐拥Windows和Xbox系统两大平台，在过去10年间一直卧薪尝胆，试图在移动终端再搭建一个新的平台。

Microsoft has two massive platforms in Windows and Xbox, and has been thrashing about for a decade trying to build one in mobile.

他卧薪尝胆，图谋报复。

He endured hardships to plan retaliation.