Definition
The essential practical details or basic components of something, rather than abstract ideas or theories.
实际细节，基本要项
Before we start this project, we need to understand the nuts and bolts of it.
在我们开始这个项目之前，我们需要了解它的基本要素。
This book delves into the nuts and bolts of economics, not just the theories.
这本书深入探讨了经济学的基本要素，而不仅仅是理论。
She is very good at dealing with the nuts and bolts of software development.
她非常擅长处理软件开发的实际细节。