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How to Insert Underline Text in LaTeX

You can write underlined text in LaTeX by using the \underline command. The text which should be underlined goes between the { and } symbol. See the example in Listing 1 in which "and parts of it" will be rendered underlined.

\documentclass{article}
\begin{document}
This is text \underline{and parts of it} are underlined.
\end{document}
Listing 1 - Underlined text in LaTeX.
A LaTeX PDF containing the underlined text
Figure 1 - A LaTeX PDF containing the underlined text.