$(1)$ $CH_3CH_2-CH_2-OH$
$(2)$ $\begin{array}{*{20}{c}}
{C{H_3} - C{H_2} - CH - OH} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}}
\end{array}$
$(3)$ $\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,C{H_3}} \\
\,\,\,\,\,\,|
\end{array}} \\
{C{H_3} - C{H_2} - C - OH} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,C{H_3}}
\end{array}$
$\begin{array}{*{20}{c}}
{C{H_3}\,\,\,} \\
{|\,\,\,\,\,\,\,\,} \\
{C{H_3} - C - CHC{H_3}} \\
{\,|\,\,\,\,\,\,\,\,\,\,|} \\
{\,\,H\,\,\,\,\,\,\,Br}
\end{array}$ $\xrightarrow{{C{H_3}OH}}$