\chapter{The second chapter}

This is a book second chapter...

\section{Section A}

This is a section A from "The second chapter"...

\section{Section B}

This is a section B from "The second chapter"...

%\subsection{''Subsection''}
%\subsubsection{''Subsubsection''}
%\paragraph{''Paragraph''}
%\subparagraph{''Subparagraph''}
