\begin{tabbing}
$M_{1}$ $\subseteq$ $M_{2}$
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$\=1of($M_{1}$) $\subseteq$ 1of($M_{2}$) \& 1of(2of($M_{1}$)) $\subseteq$ 1of(2of($M_{2}$))\+
\\[0ex]\& \=1of(2of(2of($M_{1}$))) $\subseteq$ 1of(2of(2of($M_{2}$)))\+
\\[0ex]\& 1of(2of(2of(2of($M_{1}$)))) $\subseteq$ 1of(2of(2of(2of($M_{2}$))))
\\[0ex]\& 1of(2of(2of(2of(2of($M_{1}$))))) $\subseteq$ 1of(2of(2of(2of(2of($M_{2}$)))))
\\[0ex]\& 1of(2of(2of(2of(2of(2of($M_{1}$)))))) $\subseteq$ 1of(2of(2of(2of(2of(2of($M_{2}$))))))
\\[0ex]\& 1of(2of(2of(2of(2of(2of(2of($M_{1}$))))))) $\subseteq$ 1of(2of(2of(2of(2of(2of(2of($M_{2}$)))))))
\\[0ex]\& 1of(2of(2of(2of(2of(2of(2of(2of($M_{1}$)))))))) $\subseteq$ 1of(\=2of(2of(2of(2of(2of(2of(2of(\+
\\[0ex]$M_{2}$))))))))
\-\\[0ex]\& 1of(\=2of(2of(2of(2of(2of(2of(2of(2of(\+
\\[0ex]$M_{1}$))))))))) $\subseteq$ 1of(2of(2of(2of(2of(2of(2of(2of(2of($M_{2}$)))))))))
\-\\[0ex]\& 1of(\=2of(2of(2of(2of(2of(2of(2of(2of(2of(\+
\\[0ex]$M_{1}$)))))))))) $\subseteq$ 1of(2of(2of(2of(2of(2of(2of(2of(2of(2of($M_{2}$))))))))))
\-\\[0ex]\& 1of(\=2of(2of(2of(2of(2of(2of(2of(2of(2of(2of(\+
\\[0ex]$M_{1}$))))))))))) $\subseteq$ 1of(2of(2of(2of(2of(2of(2of(2of(2of(2of(2of($M_{2}$)))))))))))
\-\-\-
\end{tabbing}