# Fix the height/length of a minipage

I have 2 columns in 1 slide. On the left hand, it is a tabbing inside a minipage in a framed. Some sentences are shown one by one by overlay, that results in the height/length of the whole minipage on the left increases gradually. I would like to fix the height/length in the beginning, and leave the place for the sentences coming up. Does anyone know how to do it?

\begin{columns}
\begin{column}
\begin{framed}
\resizebox{0.85\textwidth}{!}{%
\begin{minipage}{\textwidth}
\begin{tabbing}
...
\only<2->{sentence 2} \\
\only<3->{sentence 3} \\
\only<4->{sentence 4}
\end{tabbing}
\end{minipage}}
\end{framed}
\end{column}
\begin{column}
...
\end{column}
\end{columns}

-
  \begin{minipage}[t][10cm][t]{\textwidth}

Actually I realize that replacing \only by \onslide solves the problem... –  SoftTimur Aug 15 '12 at 17:48