% http://sip.clarku.edu/tutorials/TeX/intro.html
\documentclass[12pt]{article}

\usepackage{amsmath}    % need for subequations
\chapter{chapter text}
\include{chapter1-intro.inc}
\section{section1 text}
It is desirable to print program code exactly as it is typed in a
monospaced font. Use \verb \begin{verbatim} and
\section{Introduction}
\part{Part1}
It is desirable to print program code exactly as it is typed in a
monospaced font. Use \verb \begin{verbatim} and
\subsection{subsection2}
It is desirable to print program code exactly as it is typed in a
monospaced font. Use \verb \begin{verbatim} and
\subsubsection{subsubsection3 with extra text}
It is desirable to print program code exactly as it is typed in a
monospaced font. Use \verb \begin{verbatim} and
\section[short section4]{section4 text}
\paragraph[short para1]{long paragraph1}
\paragraph{long paragraph2}
It is desirable to print program code exactly as it is typed in a
monospaced font. Use \verb \begin{verbatim} and
\part{Part2}
\section[shorter intro2]*{Introduction2longtitle}
It is desirable to print program code exactly as it is typed in a
monospaced font. Use \verb \begin{verbatim} and
\subsection[subsec5 text]*{subsection5}
\subparagraph[short subpara1]{long subparagraph1}
\subparagraph{long subparagraph2}
It is desirable to print program code exactly as it is typed in a
monospaced font. Use \verb \begin{verbatim} and
\subsubsection{subsubsection6 with extra text}
It is desirable to print program code exactly as it is typed in a
monospaced font. Use \verb \begin{verbatim} and
\chapter{chapter2}
\include{chapter2-intro.inc}
\end{document}

