1 $\begin{array}{*{20}{c}}
{Cl\,\,\,\,\,\,\,\,\,\,\,\,}\\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,}\\
{{H_2}C = C - CH = C{H_2}}
\end{array}$
2 $\begin{array}{*{20}{c}}
{{H_2}C = C - CH = C{H_2}}\\
{\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\\
{{C_6}{H_5}\,\,\,\,\,}
\end{array}$
3 $\begin{array}{*{20}{c}}
{{H_2}C = C - CH = C{H_2}}\\
{\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\\
{C{H_3}\,\,\,\,\,\,\,}
\end{array}$
4 \((-CH_2-CH_2-)_n\)