"LaTex" write a paper, display line number

I. Introduction

When writing a paper in LaTeX, there are some very desired auxiliary functions, and the technical realization is very simple, just like a window paper that breaks with a poke.

2. Technical issues

If you see the line number in real time when writing a paper in LaTex, as shown below:

3. Technical realization

Add the following code:

\usepackage{lineno}

\begin{document}
\linenumbers

\end{document}

*Pro-test effective