Followed by Markownikoffs rule.

$C{{H}_{3}}-C{{H}_{2}}-C\equiv CH+HCl\to $

$\begin{matrix}
   C{{H}_{3}}C{{H}_{2}}-C=C{{H}_{2}}  \\
   \,\,\,\,\,\,\,\,\,\,\,|  \\
   \,\,\,\,\,\,\,\,\,\,\,\,\,Cl  \\
\end{matrix}$  $\xrightarrow{HI}$  $\underset{2\,-\,chloro\,-\,2\,-\,iodo\,bu\tan e}{\mathop{\begin{matrix}
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\begin{matrix}
   I  \\
   |  \\
\end{matrix}  \\
   C{{H}_{3}}-C{{H}_{2}}-C-C{{H}_{3}}  \\
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|  \\
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,Cl  \\
\end{matrix}}}\,$