作为一名经验丰富的程序员，她对这款软件的代码库了如指掌。

As a seasoned programmer, she ___knows the software's codebase ___inside ___out.

在产品发布前，我们的团队花了数月时间进行研究，以便对目标市场了如指掌。

Before launching the product, our team spent months researching to ___know the target market ___inside ___out.

在那里生活了二十年后，他对这座城市及其历史了如指掌。

After living there for twenty years, he ___knows the city and its history ___inside ___out.