%%
%% The LaTeX Companion, 3ed
%%
%% Example 13-4-1 on page II-330 in "The Greek alphabet".
%%
%% 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{351.0pt}
%StartShownPreambleCommands
%
  \usepackage{gfsartemisia,tabularx,booktabs}
  \usepackage[english,greek]{babel}
  \def\glyph#1{\makebox[12pt][c]{#1}}
  \setlength\parindent{0pt}
  \renewcommand\familydefault{cmr}

%StopShownPreambleCommands

\begin{document}
      \centering
      \begin{tabularx}{\linewidth}{lX}
        \toprule
      \textit{\selectlanguage{english}Input} &
      \ttfamily
        \leavevmode\selectlanguage{english}%
        \glyph{a}\glyph{b}\glyph{c}\glyph{d}\glyph{e}\glyph{f}%
        \glyph{g}\glyph{h}\glyph{i}\glyph{j}\glyph{k}\glyph{l}%
        \glyph{m}\glyph{n}\glyph{o}\glyph{p}\glyph{q}\glyph{r}%
        \glyph{s}\glyph{t}\glyph{u}\glyph{v}\glyph{w}\glyph{x}%
        \glyph{y}\glyph{z}\\[2pt]
      &
        \leavevmode\selectlanguage{greek}%
        \glyph{a}\glyph{b}\glyph{c}\glyph{d}\glyph{e}\glyph{f}%
        \glyph{g}\glyph{h}\glyph{i}\glyph{j}\glyph{k}\glyph{l}%
        \glyph{m}\glyph{n}\glyph{o}\glyph{p}\glyph{q}\glyph{r}%
        \glyph{s}\glyph{t}\glyph{u}\glyph{ }\glyph{w}\glyph{x}%
        \glyph{y}\glyph{z}\\[5pt]
      \textit{\selectlanguage{english}Input} &
        \leavevmode\selectlanguage{english}%
      \ttfamily
        \glyph{A}\glyph{B}\glyph{C}\glyph{D}\glyph{E}\glyph{F}%
        \glyph{G}\glyph{H}\glyph{I}\glyph{J}\glyph{K}\glyph{L}%
        \glyph{M}\glyph{N}\glyph{O}\glyph{P}\glyph{Q}\glyph{R}%
        \glyph{S}\glyph{T}\glyph{U}\glyph{V}\glyph{W}\glyph{X}%
        \glyph{Y}\glyph{Z}\\[2pt]
      &
        \leavevmode\selectlanguage{greek}%
        \glyph{A}\glyph{B}\glyph{C}\glyph{D}\glyph{E}\glyph{F}%
        \glyph{G}\glyph{H}\glyph{I}\glyph{J}\glyph{K}\glyph{L}%
        \glyph{M}\glyph{N}\glyph{O}\glyph{P}\glyph{Q}\glyph{R}%
        \glyph{S}\glyph{T}\glyph{U}\glyph{ }\glyph{W}\glyph{X}%
        \glyph{Y}\glyph{Z}\\
      \bottomrule
        \end{tabularx}
\end{document}