You have to know the ins and outs of the business.

你必须彻头彻尾了解这件事。

youdao

I know all the ins and outs of the business.

我知道这件事情的来龙去脉。

youdao

I know all the ins and outs of the business.

我知道这件事情的来龙去脉。

youdao