%%
%% The LaTeX Companion, 3ed
%%
%% Example 3-3-13 on page I-162 in "Using acro for abbreviations".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{75.0pt}
\setlength\parindent{0pt}
%StartShownPreambleCommands
 \usepackage{acro}
\DeclareAcronym{zB}{short=z.B\acdot,long=zum Beispiel,
                    first-style=short}
\DeclareAcronym{etc}{short=etc\acdot,long=et cetera,
                    first-style=short}
%StopShownPreambleCommands

\begin{document}
 1 \Ac*{zB},  2 \ac{zB},  \\ 3 \acl{zB},  4 \ac{zB}. \\
 1 \Ac*{etc}, 2 \ac{etc}, \\ 3 \acl{etc}, 4 \ac{etc}.
\end{document}