Multiline brace in eqnarray

I have an eqnarray that consists of 3 lines. I would like to have a right brace } that spans the last two lines and some brief text explaining t开发者_如何学Gohese two parts of the equation. Something like

foo = bar

    = baz }
          } explain
    = etc }

but using one large brace, obviously. Is this possible?

It is recommended to use align instead of eqnarray (it gives wrong spacing sometimes). Here is how it can be done with align:

\begin{align}
    foo & \left.\begin{array}{l} = bar \\ \end{array}\right. \\
        & 
    \left. \begin{array}{l}
        = baz \\
        = etc
    \end{array}\right\} explain
\end{align}

The second line's array is just to make the spacing right.

Result will be like this (but of course with equation numbers):