Latex cline

\cline


\cline{i-j}

The \cline command draws horizontal lines across the columns 
specified, beginning in column i and ending in column j, which 
are identified in the mandatory argument.

It is used in the tabular and array environment.

Two (or more) successive \cline commands draw lines in the same 
vertical position. Typically, \cline commands are placed after a 
\ (line breadk) command so that they separate items on two lines; 
they do not, however, need a line break command afterwards.

\begin{tabular}{|r|l|}
  \hline
  7C0 & hexadecimal \
  3700 & octal \ \cline{2-2}
  11111000000 & binary \
  \hline \hline
  1984 & decimal \
  \hline
\end{tabular}

produces this output