\documentclass{article}

\def\d{{\rm d}}
\def\be{\begin{equation}}
\def\ee{\end{equation}}
\def\bc#1#2{#1 oder #2}
\def\ac #1 #2{#1 und #2}
\def\bea{\begin{eqnarray}}
\def\eea{\end{eqnarray}}

\newenvironment{mathegs}%
{\medskip\footnotesize\begin{center}%
\renewcommand{\arraystretch}{1.3}
\begin{tabular}{ll}%
\it \makebox[190pt][l]{Type} & \it To produce\\}
{\end{tabular}\end{center}\medskip}

\begin{document}

\ac {abc} {bde}

\bc {ace} {gda}

\bea
\nabla \times   \vec H &=& \vec J_c + {\partial \vec D \over \partial t} \label{M1} \\
\nabla \times   \vec E &=&          - {\partial \vec B \over \partial t} \label{M2} \\
\nabla \,\cdot\,\vec D &=& \varrho_e                         \label{M3} \\
\nabla \,\cdot\,\vec B &=& 0                                 \label{M4}
\eea

this is another test
\begin{mathegs}
\verb@$a^2b^3$@ & $a^2b^3$\\
\verb@$2^{21}$@ & $2^{21}$\\
\verb@$2^21$@ & $2^21$\\
\verb@$a^{x+1}$@ & $a^{x+1}$\\
\verb@$a^{x^2+1}$@ & $a^{x^2+1}$\\
\verb@$(x+1)^3$@ & $(x+1)^3$\\
\verb@$\Gamma_{\alpha\beta\gamma}$@ & $\Gamma_{\alpha\beta\gamma}$\\
\verb@${}_1A_2$@ & ${}_1A_2$\\
\end{mathegs}


\end{document}
