1 $\begin{array}{*{20}{c}}
{^H} \\
{_H}
\end{array}\begin{array}{*{20}{c}}
\backslash \\
/
\end{array}C = O$
2 \(\mathop {\mathop {C\,\,\,\,}\limits_{|\,\,\,\,\,\,\,}^{|\,\,\,\,\,\,\,} }\limits_{\,C{H_3}}^{H\,\,\,\,\,} = \,\,\;\mathop {\mathop {\mathop C\limits_|^| \,\,\,\,\,}\limits^{C{H_3}} }\limits_{H\,\,\,\,\,} \)
3 \(\mathop {\mathop {C\,\,\,\,}\limits_{|\,\,\,\,\,\,\,}^{|\,\,\,\,\,\,\,} }\limits_{\,C{H_3}}^{C{H_3}\,\,\,\,\,} = \,\,\;\mathop {\mathop {\mathop C\limits_|^| \,\,\,\,\,}\limits^{{H}} }\limits_{H\,\,\,\,\,} \)
4 \(\mathop {\mathop C\limits_|^| \,\,\,\,\,\,}\limits_{C{H_3}\,}^{Cl\,\,\,\,\,} = \;\;\mathop {\mathop C\limits_|^| \,\,\,\,\,}\limits_{Cl\,\,\,}^{\,\,C{H_3}} \)