"know your shit" in Chinese (Traditional)
很懂行（粗俗）- 真內行（俚語）
Definition
指某人對某事非常精通或擅長，屬於非正式且帶有粗話的表達。
Usage Notes (Chinese (Traditional))
非常口語化且帶點髒話，只適合熟人或私下場合。意為非常內行且自信，不適合正式場合。
Examples
He really knows his shit when it comes to computers.
他在電腦方面真的**很懂行**。
If you want advice on cars, talk to Sam—he knows his shit.
想要關於汽車的建議，去找Sam吧——他**非常懂行**。
She knows her shit in marketing.
她在市場行銷上真的**很懂行**。
Don’t worry, our guide knows his shit—we’re in good hands.
別擔心，我們的導遊**很內行**，我們很安全。
Wow, you really know your shit about wine!
哇，你真的**很會選**葡萄酒啊！
Trust Jamie for this project—she knows her shit.
這個項目找Jamie沒錯——她**非常內行**。